What does the Symbol data type represent in JavaScript?

Which of the following statements about primitive values in JavaScript is true?

A). They are mutable

B). They are passed by reference

C). They are stored on the heap

D). They are immutable

Which symbol is used to represent a boolean value in JavaScript?

A). #

B). $

C). !

D). true/false

What happens when you try to access a variable that has not been declared in JavaScript?

A). SyntaxError is thrown

B). ReferenceError is thrown

C). TypeError is thrown

D). Undefined

What is the data type of the value undefined in JavaScript?

A). String

B). Object

C). Undefined

D). Number

What is the result of the expression 5 + '5' in JavaScript?

A). 10

B). '55'

C). '10'

D). Error

What happens when you add two numbers using the + operator in JavaScript?

A). The numbers are concatenated

B). The numbers are multiplied

C). The numbers are added

D). An error occurs

Which of the following is not a primitive value in JavaScript?

A). Number

B). Boolean

C). Object

D). String

What is a primitive value in JavaScript?

A). A complex data structure

B). A basic data type

C). A function

D). An array

What is the result of the expression undefined + null in JavaScript?

A). undefined

B). null

C). 0

D). Error

What is the result of the expression true + false in JavaScript?

A). true

B). false

C). 1

D). 0