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Question 1:  What is the main purpose of a Web Worker in JavaScript?

(A) To speed up CSS rendering

(B) To run JavaScript code in a background thread

(C) To store data in the browser cache

Question 2:  Which method is used to send messages from the main thread to a Web Worker?

(A) sendMessage()

(B) postMessage()

(C) dispatchMessage()

Question 3:  What is a Service Worker primarily used for?

(A) Creating animations in JavaScript

(B) Handling network requests and enabling offline functionality

(C) Running CSS in the background

Question 4:  Which lifecycle event of a Service Worker is triggered first when it is installed?

(A) activate

(B) install

(C) fetch

Question 5:  In a Web Worker, which global object replaces window?

(A) workerScope

(B) self

(C) this

Question 6:  Which file type is used to register a Service Worker in a web application?

(A) .sw.js

(B) .worker

(C) .json

Question 7:  How is a Web Worker terminated from the main thread?

(A) worker.close()

(B) worker.kill()

(C) worker.terminate()

Question 8:  Which of the following is NOT a capability of Service Workers?

(A) Intercepting network requests

(B) Running scripts on a separate thread

(C) Directly manipulating the DOM

Question 9:  How do you register a Service Worker in JavaScript?

(A) navigator.worker.register('sw.js')

(B) navigator.serviceWorker.register('sw.js')

(C) serviceWorker.register('sw.js')

Question 10:  Which event in Service Workers is used to handle offline caching of assets?

(A) fetch

(B) cache

(C) install