JavaScript Browser APIs | Async, Storage & Fetch (MCQs)

1. Which function runs code after a specified delay?

a) setInterval()
b) setTimeout()
c) delay()
d) wait()

2. Which function repeatedly runs code at fixed time intervals?

a) setTimeout()
b) repeat()
c) setInterval()
d) loop()

3. What is the time unit used in setTimeout and setInterval?

a) Seconds
b) Minutes
c) Milliseconds
d) Hours

4. Which method stops a running setInterval?

a) stopInterval()
b) clearInterval()
c) endInterval()
d) removeInterval()

5. Where is LocalStorage data stored?

a) Server
b) Database
c) Browser
d) Cloud

6. Which method is used to save data in LocalStorage?

a) setData()
b) saveItem()
c) setItem()
d) addItem()

7. What data type does LocalStorage store?

a) Numbers only
b) Objects only
c) Strings only
d) Arrays only

8. Which API is used to get data from a server?

a) Storage API
b) DOM API
c) Fetch API
d) Timer API

9. What does fetch() return?

a) Data directly
b) JSON object
c) Promise
d) Array

10. Which keyword is used to handle successful or failed promises?

a) then / catch
b) try / except
c) do / while
d) if / else

11. Which keyword makes asynchronous code easier to read?

a) promise
b) async / await
c) callback
d) timeout

12. What does the await keyword do?

a) Stops the browser
b) Waits for a promise to resolve
c) Creates a promise
d) Cancels a fetch request

13. Which project commonly uses LocalStorage?

a) Weather App
b) Notes App
c) Calculator
d) Clock

14. Which project uses Fetch API to get live data?

a) Counter
b) FAQ
c) Weather App
d) Dark Mode

15. Browser APIs are mainly used to:

a) Style web pages
b) Create databases
c) Interact with browser features
d) Design UI

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