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 '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
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 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 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 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();
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
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
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; };