JavaScript and CSS Basics Quiz

Which of the following is the correct way to define a function in JavaScript?

• function = myFunction() {}

• function myFunction() {}

• def myFunction() {}

• function: myFunction() {}

What does the `getElementById` method do in JavaScript?

• It selects all elements with a specific class name.

• It selects the first element with a specific tag name.

• It selects the element with a specific id.

• It creates a new element with a given id.

How can you change the content of an HTML element with the id "demo" to "Hello, World!" using JavaScript?

• document.getElementById("demo").innerHTML = "Hello, World!";

• document.getElementById("demo").value = "Hello, World!";

• document.getElementById("demo").text = "Hello, World!";

• document.getElementById("demo").content = "Hello, World!";

Which symbol is used to select a class in CSS?

• #

• .

• $

• @

How would you select an element with the id "main" in CSS?

• .main

• #main

• main

• *main

What is the correct way to add a click event handler to a button with the id "myBtn" in JavaScript?

• document.getElementById("myBtn").onclick = myFunction;

• document.getElementById("myBtn").onClick(myFunction);

• document.getElementById("myBtn").addEvent("click", myFunction);

• document.getElementById("myBtn").click = myFunction();

Which of the following is the correct syntax to select all elements with the class "highlight" in CSS?

• #highlight

• .highlight

• highlight

• *highlight

If you want to change the text inside a paragraph with id "info" to "Welcome!", which JavaScript code would you use?

• document.getElementById("info").innerHTML = "Welcome!";

• document.getElementById("info").text = "Welcome!";

• document.getElementById("info").value = "Welcome!";

• document.getElementById("info").content = "Welcome!";

Which of the following is NOT a valid way to define a function in JavaScript?

• function myFunc() {}

• var myFunc = function() {};

• let myFunc = () => {};

• define myFunc() {}

What is the main difference between a CSS class selector and an id selector?

• Class selectors are used for JavaScript only, id selectors are for CSS only.

• Class selectors use a dot (.), id selectors use a hash (#).

• Class selectors can only be used once per page, id selectors can be used multiple times.

• There is no difference.