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

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

A). #

B). $

C). !

D). true/false

Which primitive value represents absence of value or no value assigned?

A). undefined

B). null

C). 0

D). 'undefined'

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

A). undefined

B). null

C). 0

D). Error

What is a primitive value in JavaScript?

A). A complex data structure

B). A basic data type

C). A function

D). An array

Which of the following is a valid JavaScript symbol?

A). symbol

B). &symbol

C). #symbol

D). Symbol('description')

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

A). 10

B). '55'

C). '10'

D). Error

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

What is the default value of a variable in JavaScript if it is not initialized?

A). null

B). undefined

C). 0

D). 'undefined'

What does the Symbol data type represent in JavaScript?

A). A unique identifier

B). A number

C). A boolean value

D). An object

Which of the following statements is true about JavaScript's null value?

A). It represents an empty string

B). It represents a non-existent value

C). It represents a boolean value

D). It represents a number