Which operator is used for strict inequality in JavaScript?
A). !==
B). !=
C). <>
D). /=
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
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
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 '''
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();
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 is the correct way to declare a JavaScript class?
A). class Rectangle {}
B). let Rectangle = {}
C). function Rectangle() {}
D). Rectangle {}
How do you concatenate strings in JavaScript?
A). Using the + operator
B). Using the - operator
C). Using the * operator
D). Using the / operator
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