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

BA built-in JavaScript method for handling timeouts

CA callback function used for event handling

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

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));

BError thrown and stops execution

Cundefined

DCaught: Error occurred

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