CS521 MCQs File 3

**Modifying DOM Elements**

Q1. Which method is used to change the text content of an HTML element?

• a) `getElementById`
• b) `innerText`
• c) `innerHTML`
• d) `setAttribute`
• **Answer: c) innerHTML**

**Creating DOM elements**

Q2. How do you create a new HTML element in JavaScript?

• a) `document.createElement("div")`
• b) `document.newElement("div")`
• c) `createNewElement("div")`
• d) `createElement("div")`
• **Answer: a) document.createElement("div")**

**Event Handling**

Q3. Which of the following is used to attach an event handler to an element?

• a) `addEventListener`
• b) `attachEvent`
• c) `on Event`
• d) `setEvent`
• **Answer: a) addEventListener**

**Capturing and Bubbling**

Q4. Event capturing and bubbling are phases of which process?

• a) Event propagation
• b) Event delegation
• c) Event binding
• d) Event creation
• **Answer: a) Event propagation**

**Event Types**

Q5. Which event is fired when a user presses a key on the keyboard?

• a) `keydown`
• b) `keypress`
• c) `keyup`
• d) `keyclick`
• **Answer: a) keydown**

**Form Validation; Client Side Input Validation**

Q6. Which HTML attribute is used to specify that an input field must be filled out before submitting the form?

Q9. How do you hide an element using jQuery?

• a) `$("#element").hide();`
• b) `$("#element").display(false);`
• c) `$("#element").css("display", "none");`
• d) `$("#element").invisible();`
• **Answer: a) $("#element").hide();`

**Query Manipulators - Example**

Q10. Which jQuery method is used to change the HTML content of a selected element?

• a) `html()`
• b) `text()`
• c) `content()`
• d) `changeHTML()`
• **Answer: a) html()**

**Events in Query**

Q11. How do you attach a click event to a button using jQuery?

• a) `$("button").click(function() {});`