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

Answer & Solution

Answer: Option B
Solution:
In modern JavaScript, 'let' and 'const' are preferred over 'var' due to block scoping and better variable management. 'var' is function-scoped, while 'let' and 'const' are block-scoped, making them safer and more predictable in terms of variable scope. Therefore, option B is the correct way to declare a variable 'x' with an initial value of 10.
Related Questions on Average

Which statement correctly declares a JavaScript function?

A). function greet() {}

B). const greet = function() {}

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

D). const greet = {}

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

A). Type and value equality

B). Type equality only

C). Value equality only

D). Reference equality

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

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 module?

A). export function myFunc() {}

B). const myModule = function() {}

C). module.exports = myModule;

D). import myModule from './myModule.js';

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();

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

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};