How do you concatenate strings in JavaScript?
A). Using the + operator
B). Using the - operator
C). Using the * operator
D). Using the / operator
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 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');
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
What is the purpose of the 'continue' statement in a JavaScript loop?
A). To exit the loop
B). To skip the current iteration
C). To restart the loop
D). To execute the loop body again
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
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 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 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 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};