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Climate Change Review Study Guide

Total questions: 99

Worksheet time: 50mins

Name
Class
Date
1.

True/False: Select the correct option. Seasons are characterized by the position of the earth to the sun. In the summer solstice, the Southern Hemisphere is tilted toward the sun in June.

a)

true

b)

false

2.

True/False: Select the correct option. While scientists have seen an increase in atmospheric carbon dioxide, to date there has been no evidence to support the relationship between the increase of carbon dioxide and global warming.

a)

true

b)

false

3.

True/False: Select the correct option. The last 20 years have been cooler than previously because human activity has decreased.

a)

true

b)

false

4.

True/False: Select the correct option. Hurricanes and other severe precipitation events have started becoming weaker and less intense as a result of climate change.

a)

true

b)

false

5.

True/False: Select the correct option. A carbon atom can form up to three single covalent bonds with other atoms.

a)

true

b)

false

6.

True/False: Select the correct option. Climate change can influence the ecosystem levels. However, these influences do not impact the communities of organisms.

a)

true

b)

false

7.

True/False: Select the correct option. Burning fossil fuels releases O2 into the atmosphere.

a)

true

b)

false

8.

Check all that apply: Choose all options that best complete the statement or answer the question. Thinking about the evidence of climate change presented in this chapter, select from the following those factors that have decreased as a result of climate change.

a)

Humidity

b)

Sea level

c)

Sea ice

d)

Snow coverage

e)

Temperature of land

9.

Check all that apply: Choose all options that best complete the statement or answer the question. Thinking about the evidence of climate change presented in this chapter, select from the following those factors that have decreased as a result of climate change.

a)

Glaciers

b)

Sea level

c)

Temperature of land

d)

Humidity

10.

Check all that apply: Choose all options that best complete the statement or answer the question. From the list provided, select all sources of methane production.

a)

The burning of fossil fuels

b)

Livestock

c)

Decomposition of organic material

d)

Volcanic activity

11.

Check all that apply: Choose all options that best complete the statement or answer the question. Of the following, which two characteristics define climate?

a)

Temperature

b)

Amount of precipitation

c)

Tornado development

d)

High sea levels

12.

Check all that apply: Choose all options that best complete the statement or answer the question. From the list, select all that influence the average temperature of the planet.

a)

Precipitation

b)

Species becoming extinct

c)

Volcanic eruptions

d)

Cycling of the sun

13.

Check all that apply: Choose all options that best complete the statement or answer the question. Select all of the following examples of extreme weather that are strongly attributed to global climate change.

a)

An increase in the number of tornados

b)

An increase in the severity of hurricanes

c)

An increase in volcanic eruptions

d)

An increase in extreme flooding events

e)

An increase in severe droughts

14.

Check all that apply: Choose all options that best complete the statement or answer the question. Select all of the following examples of extreme weather that are strongly attributed to global climate change.

a)

Increase in heat waves

b)

Increase in wildfires

c)

Increase in hail storms

d)

Increase in the number of hurricanes

e)

Increase in cold waves

15.

Check all that apply: Choose all options that best complete the statement or answer the question. Select all of the following examples of extreme weather that are strongly attributed to global climate change.

a)

Increase in wildfires

b)

Decrease in flooding

c)

Increase in cold waves

d)

Increase in hail storms

16.

Check all that apply: Choose all options that best complete the statement or answer the question. There are two forms of geoengineering. They are ______ and ______.

a)

carbon dioxide removal

b)

solar radiation management

c)

deforestation

d)

wind harvesting

17.

Check all that apply: Choose all options that best complete the statement or answer the question. Scientists are hopeful that there are solutions to climate change. What are the three things that are required to reduce the long-term impacts of climate change?

a)

New forms of alternative energy

b)

A positive change in personal choices

c)

An increase consumption of livestock

d)

Advances in supportive technologies

18.

Check all that apply: Choose all options that best complete the statement or answer the question. Select all of the following that lower an individual's carbon footprint.

a)

Eating foods that are grown faraway in other countries

b)

Carpooling or taking public transportation

c)

Eating a diet rich in beef and dairy

d)

Heating through passive solar and geothermal energy

19.

Check all that apply: Choose all options that best complete the statement or answer the question. Select all of the common sources of alternative and renewable energy.

a)

Natural gas

b)

Solar energy

c)

Wind

d)

Oil

20.

Which of the following best describes the relationship between climate change and global warming?

a)

The terms climate change and global warming can be used interchangeably because they mean the same thing.

b)

The increase in temperature is one aspect of climate change and can result in the increased temperature of the planet, which is known as global warming.

c)

Climate change is defined only by the changing of temperature, which can result in the increased temperature of the planet known as global warming.

21.

Fires and volcanic activity are natural events that produce _____.

a)

CO2CO_2

b)

H2OH_2O

c)

CH4CH_4

d)

CFCs

22.

Since the 1950s, there has been a steady increase in the levels of atmospheric CO2CO_2 as a result of

a)

increased human activity.

b)

an increase in naturally occurring forest fires.

c)

increased volcanic activity.

23.

Methane versus carbon dioxide are very important greenhouse gases. However, methane can retain and release about ____ times more heat than carbon dioxide.

a)

10

b)

30

c)

75

d)

100

24.

Which of the following minor contributing greenhouse gases are produced from agricultural practices such as the use of burning of fossil fuels and used in fertilizers?

a)

Methane

b)

Chlorofluorocarbons

c)

Nitrous oxides

d)

Water vapor

25.

According to the evidence of climate change, there has been an overall ______ in ocean and land temperature, and an overall ______ in ice formations.

a)

increase; increase

b)

increase; decrease

c)

decrease; decrease

d)

decrease; increase

26.

Methane

a)

is a greenhouse gas.

b)

releases more heat than carbon dioxide.

c)

is less common in the atmosphere than carbon dioxide.

d)

All of the answer choices are correct.

27.

The average global temperature has always measured higher than the average since the

a)

1900s.

b)

1920s.

c)

1950s.

d)

1980s.

28.

Climate can best be described as

a)

the average weather patterns in a given area over long periods of time.

b)

the temperature and rainfall of a specific area over the course of a year.

c)

how hot or cold a location is, based on its altitude.

29.

Over the past several decades, the overall trend for earth's temperatures has been

a)

increases in overall global temperatures at an accelerating rate, a phenomenon known as global warming.

b)

cyclical periods of warming and cooling, known as global climate change.

c)

a gentle trend towards colder winters and hotter summers, which averages out to be very little overall global temperature changes.

d)

decreases in overall global temperatures at an accelerating rate, a phenomenon known as global cooling.

30.

The greenhouse effect

a)

decreases the amount of carbon dioxide in the air.

b)

increases the amount of carbon dioxide in the air.

c)

is caused by gases such as carbon dioxide trapping heat in the earth's atmosphere.

d)

is due to gases forming a barrier around the earth and insulating the earth from the sun's rays.

31.

How do greenhouse gases cause climate warming?

a)

Infrared energy from space is absorbed by greenhouse gases in the upper atmosphere, which then re-emit the heat toward the surface of the earth, causing the climate to warm.

b)

Greenhouse gases block solar energy from entering the lower level of the atmosphere.

c)

Greenhouse gases prevent radiation of infrared energy back into space, trapping the heat near the earth's surface and causing the climate to warm.

d)

Solar energy is absorbed by greenhouse gases in the upper atmosphere and re-emitted toward the earth's surface as heat, causing the climate to warm.

32.

Which of the following is the most likely cause for the sudden sharp increase in atmospheric carbon dioxide levels?

a)

Human activities, including the use of fossil fuels, changes in agricultural practices, and deforestation

b)

Natural events, including fires and volcanic activity

c)

Respiration from the earth's many living organisms

d)

Normal fluctuations in the natural levels of carbon dioxide in the atmosphere

33.

Which of the following are greenhouse gases?

a)

Carbon dioxide and oxygen

b)

Oxygen and methane

c)

Methane and carbon dioxide

d)

Nitrogen and carbon dioxide

34.

How does climate change affect earth's oceans?

a)

The pH level of the ocean will shift to a more acidic environment, leading to stress and the possible extinction of many species of shellfish and corals.

b)

The pH level of the ocean will shift to a more basic environment, leading to a decrease in overall productivity.

c)

As levels of carbon in the atmosphere increase, the amount of carbon in the ocean decreases proportionately.

d)

Excess carbon in the atmosphere is absorbed by the ocean, which directly increases ocean temperature.

35.

Why is ocean acidification problematic for some marine life?

a)

It decreases the amount of carbonate in the oceans, making the creation of shells and other hard structures difficult for marine life.

b)

The acidification causes metals to precipitate out of the water and deposit on the backs of aquatic organisms.

c)

It decreases the availability of oxygen in the water for the respiration needs of aquatic organisms.

d)

It decreases the stratification of water temperatures, so that marine organisms have smaller ranges in which to survive.

36.

As global temperatures increase, which of the following scenarios are most likely to happen?

a)

Sea surface temperatures and ocean heat content decrease.

b)

Glaciers and snow coverage decrease.

c)

Extreme weather events decrease.

d)

Temperatures and humidity decrease.

37.

Carbon sinks are reservoirs that hold large amounts of carbon. Which of the following are considered to be carbon sinks?

a)

Oceans

b)

Fossil fuels deep underground

c)

The atmosphere

d)

All of the answer choices are correct.

38.

Which of the following acts as a source of carbon dioxide within the carbon cycle?

a)

Respiration from humans and animals

b)

Photosynthesis by plants

c)

Fossil fuel formation

d)

Sedimentation

39.

_____ is a product of photosynthesis and is a carbon-based molecule that is the chief source of energy for most organisms.

a)

Oxygen

b)

Sucrose

c)

Glucose

d)

Carbon dioxide

40.

Photosynthesis takes carbon in from the atmosphere and uses it to form ______, the energy source for all plants and animals to use in cellular respiration.

a)

carbon dioxide

b)

glucose

c)

carbon monoxide

d)

water

41.

The light reactions of photosynthesis occur within the ______ of the chloroplast and the Calvin cycle reactions occur within the ______ of the chloroplast.

a)

thylakoid; stroma

b)

stroma; thylakoid

c)

thylakoid; outer membrane

d)

stroma; outer membrane

42.

Which statement below best summarizes the overall purpose of the light-dependent reactions?

a)

The light-dependent reactions capture the energy from the sun and transfer it to high-energy molecules.

b)

The light-dependent reactions capture the energy from the sun and convert it to glucose.

c)

The light-dependent reactions use energy to convert carbon dioxide into carbohydrate molecules.

d)

The light-dependent reactions convert high-energy molecules into carbohydrates.

43.

According to this figure, the extent of Arctic sea ice has ____ compared to the 1981–2010 median value.

a)

decreased

b)

increased

c)

cycled up and down

d)

remained consistent

44.

At the end of November of 2024, the extent of Arctic sea ice had decreased about ____ million square kilometers compared to the 1981–2010 median.

a)

0.5

b)

1.0

c)

1.5

d)

2.5

45.

What is the main difference in the formation of coal vs. the formation of natural gas and oil?

a)

Natural gas and oil formed mainly from deposits of plants and animals living in oceans and coal formed mainly from the remains of plants and animals in swampy anoxic environments.

b)

Coal formed mainly from deposits of plants and animals living in oceans and natural gas and oil formed mainly from the remains of plants and animals in swampy anoxic environments.

c)

Natural gas and oil require intense heat and pressure to form and coal only requires an anoxic environment.

d)

Coal takes several million years to form and natural gas and oil take much less time, roughly several thousand years.

46.

Because fossil fuels are the remains of once living organisms, they contain reservoirs of ______ that are released into the atmosphere when they are burned.

a)

carbon

b)

oxygen

c)

nitrogen

d)

phosphorus

47.

As climate change continues, the prevalence of vector-borne disease has increased. Why is this?

a)

As climates have warmed and winters have become less severe, the range of mosquitos and ticks has increased, bringing with them the diseases they carry.

b)

Diseases are more contagious in warmer weather, so as climates have warmed, vector-borne diseases spread faster.

c)

The bacteria and viruses that cause disease multiply more rapidly in warmer weather, so as climates have warmed, the pathogens that cause disease are more prevalent.

d)

As climates have changed, habitats have changed. Organisms that carry disease have been displaced from their original habitats and have found new habitats, bringing the spread of disease with them.

48.

How do invasive species impact ecosystems?

a)

They occupy niches that other organisms traditionally occupy.

b)

They outcompete other organisms for limited resources.

c)

They are more capable of adapting to rapidly changing climates.

d)

All of the answer choices are correct.

49.

When it comes to the carbon footprint, because of its required usage of land, ______ is the most costly food source.

a)

beef

b)

chicken

c)

lamb

d)

vegetables

50.

Which of the following would fall under the definition of an alternative energy?

a)

Coal

b)

Oil

c)

Natural gas

d)

Solar energy

51.

If a scientist was studying methods to reduce the heating of Earth by reducing the amount of solar energy that reaches Earth, this scientist would be studying

a)

solar radiation management.

b)

carbon dioxide removal.

c)

greenhouse gas management.

d)

methane remediation.

52.

What are the two most important insect vectors involved in the spread of bacterial and viral diseases?

a)

Mosquitoes and ticks

b)

House flies and ticks

c)

Roaches and house flies

d)

Fleas and mosquitoes

53.

Hemlock trees support life of other organisms. Climate change has increased the rate of infection of Hemlocks with woolly adelgid. These insects kill the trees, which decreases the habitat of animals and other insects. This is an example of how climate change impacts the

a)

individual level.

b)

population level.

c)

community level.

d)

ecosystem level.

54.

Which of the following have scientists shown to be the link between climate change and the survival rate of invasive species?

a)

The ability to produce large amounts of offspring during one birth

b)

The ability to resist toxins

c)

The ability to adapt to changing environmental conditions

d)

All of the answer choices are correct.

55.

The decrease in the ocean's pH is called ocean acidification. What impact has this had on shellfish?

a)

Their eggs are not fully developed.

b)

Their shells are weak due to the lack of calcification.

c)

Their offspring are misformed.

d)

They have become more prone to diseases.

56.

A biome is defined by its

a)

average temperature and precipitation.

b)

animals and forestry.

c)

elevation and temperature.

d)

animals and precipitation.

57.

A(n) ______ represents the interactions of biological communities and the abiotic factors within the inhabited location.

a)

ecosystem

b)

organism

c)

community

d)

population

58.

Which of the following is evidence that weather patterns have changed because of climate change?

a)

An increase in average temperature

b)

An increase in average precipitation in the central and northeast areas

c)

A decrease in precipitation in the west and southeast areas

d)

All of the answer choices are correct.

59.

Which of the following best describes the effects climate change is having on tropical reef biomes?

a)

The increase in water temperature disrupts the algae-coral symbiotic relationship, which results in death to the coral reefs.

b)

The decrease in water temperature disrupts the algae-coral symbiotic relationship, which results in death to the algae.

c)

The amount of water available for reef formation has diminished, which also kills the living coral reef beds.

60.

The measure of the impact on climate change by a person or a company is known as their

a)

carbon footprint.

b)

geocycling.

c)

carbon cycling.

d)

carbon recycling.

61.

Which of the following produces the greatest amount of carbon emissions and has the greatest impact on the human carbon footprint?

a)

Driving cars powered by gasoline

b)

Driving cars powered by electricity

c)

Wind powered energy

d)

Solar panel energy

62.

Which of the following diets would contribute to the lowest carbon footprint?

a)

Vegan (only eating vegetable-based foods)

b)

Vegetarian (eating vegetables and eggs)

c)

Omnivore (eating vegetables and meats)

63.

Desertification is an example of a biome level change that is associated with climate change. Which of the following is associated with desertification?

a)

Decreases in temperature

b)

Increases in precipitation

c)

Poor agricultural practices, including the overgrazing of cattle

d)

Conversion of deserts to grasslands

64.

Which of the following sources of alternative energy involves using uranium or other materials to split the nucleus of an atom?

a)

Nuclear energy

b)

Geothermal energy

c)

Hydroelectric energy

d)

Wind turbines

65.

The carbon cycle includes

a)

CaCO3 sedimentation in the ocean.

b)

the decay of dead organisms and their waste.

c)

photosynthesis and respiration.

d)

All of the answer choices are correct.

66.

Carbon cycles naturally between

a)

geologic and atmospheric reservoirs.

b)

geologic and atmospheric reservoirs and living organisms.

c)

atmospheric reservoirs and living organisms.

d)

geologic reservoirs and living organisms.

67.

In the carbon cycle, the process of photosynthesis ______ atmospheric CO2, and cellular respiration ______ atmospheric CO2.

a)

produces; consumes

b)

produces; produces

c)

consumes; produces

d)

consumes; consumes

68.

Which part of solar energy is important in photosynthesis?

a)

The visible spectrum of light

b)

Infrared wavelengths

c)

X-rays

69.

Sunlight consists of a wave and a particle. The particle is also known as a(an)

a)

photon.

b)

pigment.

c)

spectrum.

d)

wavelength.

70.

What two products of the light reaction are used in the Calvin cycle?

a)

O2O_2 and ATP

b)

ATP and NADPH

c)

NADPH and CO2CO_2

d)

O2O_2 and CO2CO_2

71.

Fossil fuels play a role in the carbon cycle

a)

by containing the remains of organic material.

b)

by releasing CO2CO_2 when it is burned.

c)

by being a source of coal, oil, and natural gas.

d)

All of the answer choices are correct.

72.

Even though there are alternate energy sources, fossil fuels are used for approximately ______ of the United States energy needs.

a)

22%

b)

53%

c)

84%

d)

93%

73.

Coal is a fossil fuel that results from pressure being exerted on plant and animal decay for millions of years. Oil and natural gas are also fossil fuels except they

a)

formed from microscopic plants and animals living in oceans.

b)

continue to be recharged at a rapid rate.

c)

form much faster than coal.

d)

do not require pressure to be exerted.

74.

Fossil fuels are brought up from the bottom of the ocean by

a)

the rotation of the Earth.

b)

shifting of the Earth's crust.

c)

the changing of the tides.

d)

All of the answer choices are correct.

75.

Which of the following processes contributes the greatest amount of CO2CO_2 to the atmosphere?

a)

Photosynthesis

b)

Cellular respiration

c)

The burning of fossil fuels

d)

Agriculture

76.

Climate change influences individuals and species by

a)

increasing the spread of diseases.

b)

causing droughts and heat waves.

c)

decreasing the amount of habitat available to animals.

d)

All of the answer choices are correct.

77.

Climate change has resulted in droughts and heat waves. What is the major consequence of droughts and heat waves to humans in the United States?

a)

The increase in the spread of diseases and incidence of tornadoes

b)

Downed power lines and increased algal growth

c)

Disruption to agriculture and increased death rate

d)

Increased precipitation and flooding

78.

Evolution is a natural process that occurs over time. Evolution has been disrupted by climate change because the changes are occurring at such a rapid rate,

a)

species are not able to adapt to the changes fast enough.

b)

organisms die before they are born.

c)

mutations occur within the gene pool.

d)

the weaker organisms survive.

79.

Why is solar energy considered to be a better option in mitigating climate change?

a)

It releases far less carbon dioxide into the atmosphere compared to burning fossil fuels.

b)

It absorbs the sun's rays, preventing them from heating up the earth.

c)

It absorbs greenhouse gases, preventing them from causing heat to be trapped in the earth's atmosphere.

d)

It removes carbon dioxide from the atmosphere as it travels to Earth's surface.

80.

Which of the following is considered to be a "clean" energy source?

a)

Geothermal energy

b)

Nuclear power

c)

Burning natural gas

d)

Burning coal

81.

Which of the following is true regarding the benefits of wind energy?

a)

Considered to be a nonrenewable resource

b)

Considered to be nonpolluting

c)

Tend to be extremely cost-efficient and inexpensive to manufacture

d)

All of the answer choices are correct.

82.

Which of the following describes a disadvantage of nuclear energy, especially compared to other alternative energy sources?

a)

Nuclear energy releases large amounts of carbon dioxide into the atmosphere.

b)

Nuclear energy is not always safe because of the radioactivity involved.

c)

Nuclear energy does not actually produce much energy.

d)

Nuclear energy is not feasible on a large scale and tends to be more efficient for powering individual homes.

83.

Which of the following sources of alternative energy involves using uranium or other materials to split the nucleus of an atom?

a)

Nuclear energy

b)

Geothermal energy

c)

Hydroelectric energy

d)

Wind turbines

84.

In what way is new technology beneficial as we work to mitigate climate change?

a)

Technologies that require large-scale implementation require more funding than may be available.

b)

The long-term effects of some technological solutions may be unknown.

c)

The public often needs to be convinced of long-term changes to their way of life.

d)

Many technologies have the potential to reduce the impacts of the greenhouse effect and prevent climate change from getting any worse.

85.

Which of the following examples best describes how geoengineering may help mitigate global climate change?

a)

Developing ways to reflect portions of solar energy before they reach the earth, preventing it from contributing to the greenhouse effect

b)

Genetically engineering plants to decrease their uptake of carbon dioxide, helping to allow carbon dioxide to be sequestered in the atmosphere

c)

Genetically engineering plants to require more water for photosynthesis to occur

d)

Developing ways to create carbon sources out of the soil and ocean so that carbon is cycled more rapidly

86.

Agricultural crops are being genetically engineered to be more tolerant of climate change. Which of the following describes a change that would help crops be more tolerant of climate change?

a)

Engineer crops to withstand extremely hot temperatures.

b)

Engineer crops to be intolerant of colder temperature ranges.

c)

Engineer crops that require extra water.

d)

Engineer crops that are less nutritious.

87.

What gas has been steadily increasing in atmospheric concentration and contributes greatly to the greenhouse effect due to its ability to absorb infrared energy?

a)

Sulfur dioxide

b)

Water vapor

c)

CFC

d)

CO2CO_2

88.

In the Calvin Cycle reaction, how would you describe the regeneration of RuBP?

a)

3CO23CO_2 molecules react with 3 RuBP molecules to form 6 3PG molecules

b)

6 ATP molecules are dephosphorylated and 6 NADPH molecules are oxidized, which results in 6 BPG molecules

c)

3 phosphates from 3 ATP molecules are added to 5 G3P molecules

89.

In the Calvin Cycle reaction, how would you describe CO2CO_2 fixation?

a)

3CO23CO_2 molecules react with 3 RuBP molecules to form 6 3PG molecules

b)

6 ATP molecules are dephosphorylated and 6 NADPH molecules are oxidized, which results in 6 BPG molecules

c)

3 phosphates from 3 ATP molecules are added to 5 G3P molecules

90.

In the Calvin Cycle reaction, how would you describe CO2CO_2 reduction?

a)

3CO23CO_2 molecules react with 3 RuBP molecules to form 6 3PG molecules

b)

6 ATP molecules are dephosphorylated and 6 NADPH molecules are oxidized, which results in 6 BPG molecules

c)

3 phosphates from 3 ATP molecules are added to 5 G3P molecules

91.

What is the source for geothermal energy?

a)

Underground heat generated by the Earth

b)

Cellulose and hemicellulose molecules in biomass

c)

Radioactive waste

d)

Hydrogen ions ( H+H^+ )

92.

Fill in the blank: The average temperature of the planet has been increasing since the 1980s. This phenomenon is called ________.

a)

global warming

b)

the ozone hole

c)

El Niño

d)

urbanization

93.

Fill in the blank: The term anthropogenic climate change is used to describe the ______-climate relationship.

a)

human

b)

animal

c)

ocean

d)

solar

94.

Fill in the blank: Using plants to create “carbon sinks” to decrease the amount of atmospheric carbon is called ______ technology.

a)

green

b)

nuclear

c)

digital

d)

combustion

95.

Fill in the blank: The phenomenon called ______ is due to the impact of climate change that is killing miles of coral reefs in the tropics.

a)

coral bleaching

b)

ocean acidification

c)

upwelling

d)

red tides

96.

Fill in the blank: Carbon molecules can form long chains called ______.

a)

polymers

b)

ions

c)

isotopes

d)

crystals

97.

Essay prompt converted to MCQ: Wind is an alternate energy source. Which option best states one pro and one con of using it instead of fossil fuels?

a)

Produces no direct air pollution but is intermittent and depends on weather

b)

Is always available and cheap to store but emits more greenhouse gases

c)

Requires no land area but causes more acid rain than coal

d)

Generates more steady baseload power than fossil fuels but releases mercury

98.

Essay prompt converted to MCQ: How has the woolly adelgid invasion affected the trout population?

a)

Trout numbers decline because loss of hemlock shade warms streams and degrades habitat

b)

Trout numbers increase because needle drop adds nutrients that boost algae and food webs

c)

Trout populations show no change because they do not rely on forested streambanks

d)

Trout migrate to saltwater where they thrive away from affected forests

99.

Essay prompt converted to MCQ: Hydrocarbons may contain functional groups to form organic molecules. Which pair lists two of the four major classes of organic molecules found in all living organisms?

a)

carbohydrates and proteins

b)

vitamins and minerals

c)

steroids and trace metals

d)

water and salts