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.
Related Questions on Average

What is the purpose of the 'constructor' method in a JavaScript class?

A). To create new instances of the class

B). To initialize class properties

C). To define class methods

D). To define class inheritance

Which statement correctly declares a JavaScript object?

A). let person = {name: 'John', age: 30};

B). const person = ('name' => 'John', 'age' => 30);

C). const person = ['name', 'John', 'age', 30];

D). var person = {name: 'John', age: 30};

What is the correct way to declare a variable in JavaScript?

A). var x = 10;

B). let x = 10;

C). const x = 10;

D). variable x = 10;

How can you comment a single line of code in JavaScript?

A). // This is a comment

B). <!-- This is a comment -->

C). /* This is a comment */

D). ''' This is a comment '''

How do you access the last element of a JavaScript array?

A). colors[colors.length - 1];

B). colors.last();

C). colors[-1];

D). colors.getLast();

Which statement correctly declares a JavaScript arrow function?

A). const add = (a, => a + b;

B). function add(a, { return a + b; }

C). const add = function(a, { return a + b; }

D). let add = function(a, { return a + b; };

What is the purpose of the 'return' statement in a JavaScript function?

A). To end the function execution

B). To return a value from the function

C). To print a value to the console

D). To declare a variable

What is the purpose of the 'this' keyword in JavaScript?

A). To refer to the current HTML element

B). To refer to the current JavaScript file

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D). To refer to the current function

Which operator is used for strict inequality in JavaScript?

A). !==

B). !=

C). <>

D). /=

How can you add a new element to the end of a JavaScript array?

A). colors.push('blue');

B). colors.add('blue');

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