Async/Await

Preview — 3 of 10 questions

What best describes a Promise in JavaScript?

javascript

const promise = new Promise((resolve, reject) => {
  setTimeout(() => resolve("Done!"), 1000);
});

promise.then((result) => console.log(result)); // "Done!" after 1s

AA function that always executes asynchronously

BAn object representing the eventual completion or failure of an asynchronous operation

CA callback function used for event handling

DA built-in JavaScript method for handling timeouts

What are the three possible states of a Promise?

APending, Resolved, Rejected

BInitial, Processing, Completed

CPending, Fulfilled, Rejected

DLoading, Success, Failure

What will the following code output?

javascript

Promise.resolve(1)
  .then((value) => value + 1)
  .then((value) => {
    throw new Error("Error occurred");
  })
  .catch((error) => console.log("Caught:", error.message));

BCaught: Error occurred

Cundefined

DError thrown and stops execution

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