Which of these is a complex or reference data type in JavaScript?

What will let x = '10'; let y = x - 5; console.log(y); output in JavaScript?

A). '5'

B). 5

C). '10'

D). 10

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

A). Object

B). Array

C). Function

D). Boolean

What is the result of 0 / 0 in JavaScript?

A). Infinity

B). 0

C). NaN

D). 1

What is the data type of the value 'null' (with quotes) in JavaScript?

A). String

B). Number

C). Null

D). Undefined

Which data type represents an intentional absence of any value in JavaScript?

A). Null

B). Undefined

C). String

D). Number

Which of the following is not a valid data type in JavaScript?

A). Array

B). Symbol

C). Map

D). Tuple

What will the following code snippet output: let a = 10; a += '5'; console.log(a); in JavaScript?

A). '105'

B). 105

C). 15

D). '15'

Which data type represents unique and immutable values in JavaScript introduced in ES6?

A). Symbol

B). Object

C). Array

D). Function

Which data type represents a block of reusable code in JavaScript?

A). String

B). Object

C). Function

D). Number

What is the data type of the value 42 in JavaScript?

A). String

B). Boolean

C). Number

D). Null