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

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'

What is the result of 0 / 0 in JavaScript?

A). Infinity

B). 0

C). NaN

D). 1

What is the outcome of typeof undefined in JavaScript?

A). String

B). Undefined

C). Null

D). Number

What will be the result of typeof 'hello' in JavaScript?

A). String

B). Number

C). Undefined

D). Function

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

A). Symbol

B). Object

C). Array

D). Function

Which operator checks if an object is an instance of a specific object type in JavaScript?

A). instanceof

B). typeof

C). isInstanceof

D). isTypeOf

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 'null' (with quotes) in JavaScript?

A). String

B). Number

C). Null

D). Undefined

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

A). Number

B). Boolean

C). String

D). Undefined

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

A). '5'

B). 5

C). '10'

D). 10