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

Which of the following is a primitive data type in JavaScript?

A). Array

B). Object

C). Function

D). String

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

A). undefined

B). null

C). 0

D). Error

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

A). Number

B). Boolean

C). Object

D). String

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

A). true

B). false

C). 1

D). 0

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

A). Number

B). String

C). Object

D). Undefined

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

A). undefined

B). null

C). 0

D). 'undefined'

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

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

A). 10

B). '55'

C). '10'

D). Error

What does the Symbol data type represent in JavaScript?

A). A unique identifier

B). A number

C). A boolean value

D). An object

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

A). null

B). undefined

C). 0

D). 'undefined'