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

Which statement correctly declares a JavaScript array?

A). let colors = ['red', 'green'];

B). const colors = {'red', 'green'};

C). const colors = ['red', 'green'];

D). var colors = ('red', 'green');

Which method is used to remove the last element from a JavaScript array?

A). colors.pop();

B). colors.removeLast();

C). colors.splice(-1, 1);

D). colors.deleteLast();

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 JavaScript class?

A). class Rectangle {}

B). let Rectangle = {}

C). function Rectangle() {}

D). Rectangle {}

Which statement correctly declares a JavaScript function?

A). function greet() {}

B). const greet = function() {}

C). const greet = () => {}

D). const greet = {}

How can you convert a string to a number in JavaScript?

A). parseInt('10')

B). parseFloat('10.5')

C). Number('10')

D). All of the above

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;

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

C). To refer to the current object

D). To refer to the current function

What does the '===' operator check in JavaScript?

A). Type and value equality

B). Type equality only

C). Value equality only

D). Reference equality

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();