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

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

A). undefined

B). NULL

C). null

D). None of the above

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

A). Number

B). String

C). Object

D). Undefined

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 true == 1 in JavaScript?

A). true

B). false

C). Error

D). 1

What is a primitive value in JavaScript?

A). A complex data structure

B). A basic data type

C). A function

D). An array

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 is the data type of the value undefined in JavaScript?

A). String

B). Object

C). Undefined

D). Number

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

A). Array

B). Object

C). Function

D). String

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 true + false in JavaScript?

A). true

B). false

C). 1

D). 0