Nanobots

In the first paragraph, the writer says that the nano-spider

• is much thicker than a human hair.

• cannot be seen under a microscope.

• was invented by an individual scientist.

• is an extremely small machine.

Why does the writer suggest nano-spiders can be classified as robots?

• because they have the features of a robot.

• because they can walk.

• because they are built with computer chips.

• because they are microscopic devices.

What does 'this' refer to in line 30?

• the number of steps DNA walkers can manage.

• the walking distance a DNA walker can do.

• the length of the DNA walkers.

• the time each step takes for a DNA walker.

What do we learn about nano-spiders in the fifth paragraph?

• They could protect our bodies from disease in future.

• They are already being used to fight cancer.

• They have been used for various medical purposes in the past.

• They have not actually been invented yet.

What does the writer say about arguments against the use of nanotechnology?

• People are concerned that it is used to build computer parts.

• People are concerned that nano-products are not tested before they are sold.

• There are concerns about whether the industry has strict rules for safety.

• There are no concerns about nanotechnology in medicine.

All in all, the writer presents nanobots as devices which

• we should be afraid of.

• have already been in use for many years.

• may be very useful in the future.

• are mainly useful in industry.