Q
How is the Undefined data type different from the Null data type in JavaScript?

Answer & Solution

Answer: Option A
Solution:
The Undefined data type represents variables that have been declared but not assigned a value, while Null represents an intentional absence of value or an explicitly cleared/reset value.
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Which primitive data type in JavaScript represents integers and floating-point numbers?

A). Number

B). String

C). Boolean

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Which primitive data type represents variables that are declared but not initialized?

A). Number

B). String

C). Undefined

D). Null

What does the expression typeof true return in JavaScript?

A). number

B). string

C). boolean

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Which primitive data type represents variables that have been explicitly set to represent no value?

A). Number

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What is the result of the expression typeof 'Hello' in JavaScript?

A). number

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Which of the following statements accurately describes the Boolean data type in JavaScript?

A). It represents textual data

B). It represents numeric data

C). It represents logical values

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What is the result of the expression typeof undefined in JavaScript?

A). number

B). string

C). undefined

D). boolean

What does the expression typeof '123' return in JavaScript?

A). number

B). string

C). undefined

D). boolean

How is the Symbol data type different from other primitive data types in JavaScript?

A). Symbols can be used as object keys

B). Symbols can be compared directly

C). Symbols can be used in mathematical operations

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Which data type is represented by the value null in JavaScript?

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