Which statement accurately describes JavaScript event bubbling?
A). A. It refers to the downward propagation of events from parent elements to child elements.
B). B. It refers to the upward propagation of events from child elements to parent elements.
C). C. It refers to the simultaneous firing of multiple events on the same element.
D). D. It refers to the automatic removal of event listeners after an event is triggered.
What is the primary purpose of JavaScript functions?
A). A. To style web pages
B). B. To provide structure to HTML elements
C). C. To create reusable code blocks
D). D. To define CSS styles for HTML
What is the purpose of the onclick attribute in HTML elements?
A). A. To define styles for HTML elements
B). B. To attach event listeners for mouse clicks
C). C. To insert JavaScript code directly into HTML
D). D. To create animations for HTML elements
Which of the following correctly defines a JavaScript function?
A). A. function addNumbers(num1, num2) { return num1 + num2; }
B). B. function = addNumbers(num1, num2) { return num1 + num2; }
C). C. function addNumbers(num1 + num2) { return num1 + num2; }
D). D. function addNumbers(num1, num2) => { return num1 + num2; }
What is the purpose of the removeEventListener() method in JavaScript?
A). A. To add event listeners to HTML elements
B). B. To detach event listeners from HTML elements
C). C. To prevent event propagation in event handling
D). D. To modify HTML content dynamically
What is the purpose of the onmouseover event in HTML?
A). A. To detect when an element is hovered over
B). B. To track changes in form inputs
C). C. To determine when an element is loaded
D). D. To handle form submissions
Which event occurs when a user submits an HTML form?
A). A. onsubmit
B). B. onmouseover
C). C. onkeydown
D). D. onclick
Which event is triggered when a web page finishes loading?
A). A. onload
B). B. onsubmit
C). C. onmouseover
D). D. onclick
Which event is triggered when a user clicks on an HTML element?
A). A. onhover
B). B. onsubmit
C). C. onload
D). D. onclick
Consider the following HTML code: Which JavaScript code adds a click event listener to the button?
A). A. document.getElementById('myButton').onclick = function() { alert('Button clicked'); };
B). B. document.getElementById('myButton').addEventListener('click', function() { alert('Button clicked'); });
C). C. document.getElementById('myButton').click(function() { alert('Button clicked'); });
D). D. document.getElementById('myButton').on('click', function() { alert('Button clicked'); });