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};
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; };
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 '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 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 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');
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 '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 correct way to declare a JavaScript class?
A). class Rectangle {}
B). let Rectangle = {}
C). function Rectangle() {}
D). Rectangle {}
What is the purpose of the 'return' statement in a JavaScript function?
A). To end the function execution
B). To return a value from the function
C). To print a value to the console
D). To declare a variable