Which of the following is a valid way to represent the value null in JavaScript?

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

A). 10

B). '55'

C). '10'

D). Error

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

A). Array

B). Object

C). Function

D). String

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 does the Symbol data type represent in JavaScript?

A). A unique identifier

B). A number

C). A boolean value

D). An object

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

A). undefined

B). null

C). 0

D). 'undefined'

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

A). Number

B). Boolean

C). Object

D). String

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

A). null

B). undefined

C). 0

D). 'undefined'

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

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

A). Number

B). String

C). Object

D). Undefined

What is the result of the expression true == 1 in JavaScript?

A). true

B). false

C). Error

D). 1