Functions in JavaScript Quiz

What is a function in JavaScript?

• A type of variable in JavaScript

• A block of code that can be defined and then called or invoked to perform a particular task.

• A built-in method for arrays in JavaScript

• A form of conditional statement in JavaScript

What are parameters in a JavaScript function?

• Variables that store the function's output

• Placeholders for the values that are passed into the function when it is called

• Comments within the function that explain its purpose

• Conditions that determine when the function is executed

How do you call a function in JavaScript?

• By using the function name followed by square brackets

• By using the function name followed by parentheses and any required arguments

• By using the function name followed by a comma

• By using the function name followed by a semicolon

What is the return statement used for in a JavaScript function?

• To declare a new variable

• To print a message to the console

• To specify the value that a function should return

• To stop the execution of the function

What is the difference between function declaration and function expression in JavaScript?

• Function declaration is hoisted and can be called before it is defined, while function expression is not hoisted and cannot be called before it is defined.

• Function declaration and function expression are the same thing in JavaScript.

• Function declaration is not hoisted and cannot be called before it is defined, while function expression is hoisted and can be called before it is defined.

• Function declaration and function expression both need to be defined before they can be called.

What is a callback function in JavaScript?

• A callback function in JavaScript is a function that is called at the beginning of the program

• A callback function in JavaScript is a function that is never executed

• A callback function in JavaScript is a function that is passed as an argument to another function and is executed after a certain event or action occurs.

• A callback function in JavaScript is a function that can only be used with arrow functions

What is the purpose of the 'this' keyword in a JavaScript function?

• To refer to the object that is executing the current function.

• To stop the function from executing

• To refer to the parent function

• To create a new object in the function

Explain the concept of function scope in JavaScript.

• Variables declared inside a function are accessible globally

• Variables declared inside a function are only accessible within that function.

• Variables declared inside a function are automatically hoisted to the top of the script

• Variables declared inside a function are only accessible outside that function