Q
What is the purpose of the 'typeof' operator in JavaScript?

Answer & Solution

Answer: Option B
Solution:
The 'typeof' operator in JavaScript is used to check the data type of a variable or an expression. It returns a string indicating the data type of the operand. For example, 'typeof 42' will return 'number', and 'typeof 'hello'' will return 'string'. Therefore, option B correctly explains the purpose of the 'typeof' operator in JavaScript.
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