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

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

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

A). Type and value equality

B). Type equality only

C). Value equality only

D). Reference equality

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';

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 array?

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

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

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

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

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 {}

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 concatenate strings in JavaScript?

A). Using the + operator

B). Using the - operator

C). Using the * operator

D). Using the / operator