Q
What is the correct way to declare a JavaScript class?

Answer & Solution

Answer: Option A
Solution:
Option A correctly declares a JavaScript class named 'Rectangle' using the 'class' keyword followed by curly braces {}. This is the modern ES6 syntax for declaring classes in JavaScript. Options B, C, and D are incorrect ways of declaring a class. Option B is an object declaration, option C is a constructor function, and option D is invalid syntax for a class declaration.
Related Questions on Average

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

Which statement correctly declares a JavaScript function?

A). function greet() {}

B). const greet = function() {}

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

D). const greet = {}

What is the purpose of the 'break' statement in a JavaScript switch case?

A). To continue to the next case

B). To exit the switch statement

C). To restart the switch statement

D). To execute the default case

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

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

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

C). colors.insert('blue', colors.length);

D). colors[colors.length] = 'blue';

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};

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();

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 purpose of the 'continue' statement in a JavaScript loop?

A). To exit the loop

B). To skip the current iteration

C). To restart the loop

D). To execute the loop body again

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

A). To check if a variable is defined

B). To check the data type of a variable

C). To assign a data type to a variable

D). To increment the value of a variable

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;