How do you concatenate strings in JavaScript?
A). Using the + operator
B). Using the - operator
C). Using the * operator
D). Using the / operator
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
How can you prevent a JavaScript function from executing immediately?
A). Using async/await
B). Using the defer attribute in HTML script tag
C). Wrapping the function in parentheses
D). Using the setTimeout function
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
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
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 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';
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 '''
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';