Download Latest JavaScript-Developer-I Questions

Comprehensive and Detailed Explanation:

Errors thrown inside setTimeout callbacks occur asynchronously, in a different tick of the event loop. A try...catch around setTimeout itself (as in D) cannot catch errors thrown later in the scheduled callback.

To catch errors from countSheep() when it’s called asynchronously, the try...catch must wrap the call inside the timeout callback:

setTimeout(function() {

try {

countSheep();

} catch (e) {

handleError(e);

}

}, 1000);

B uses finally incorrectly and references e out of scope.

C is not valid JavaScript syntax.

D’s catch can only handle synchronous errors thrown before setTimeout returns, not those thrown inside the callback.

ES Modules follow these rules:

Default exports are imported using:

import anyName from ' module '

The name chosen in the import does NOT need to match the exported name.

If a module exports:

export default function printDate() {}

then consuming code should import the function directly:

import printDate from ' /path/DatePrettyPrint.js ' ;

To execute it:

printDate();

Option analysis:

A incorrect: import DatePrettyPrint() is invalid syntax. Also calling printDate() without importing it is incorrect.

B incorrect: A default export imported as DatePrettyPrint gives the function itself, not an object containing methods. You cannot call DatePrettyPrint.printDate().

C incorrect: Imports printDate but then calls DatePrettyPrint.printDate(), which does not exist.

D correct: Correct import of a default-exported function. Correct direct invocation.

JavaScript Knowledge References (text-only)

Default export → imported without braces.

Importing default functions gives a callable function, not an object.

Correct syntax: import identifier from " module " .

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Browsers often cache JavaScript, CSS, and HTML. This means:

The developer may be running with the latest version (often with cache disabled in DevTools).

The tester may still be loading an older, cached version of the page where the background-change logic does not exist.

To ensure they are actually testing the latest deployed code:

Disabling cache (A) in the tester’s browser (usually via DevTools → Network → “Disable cache”) forces fresh loading of all resources on each refresh.

Clearing cache (C) removes older resources from the browser so the next load fetches fresh files from the server.

Options B and D do not directly help verify the tester is using the latest code:

B checks the developer’s own browser, which is not the environment showing the problem.

D suggests reworking the code before confirming whether the tester is actually loading the correct version, which is premature.

So the two actions that help produce accurate testing results are A and C.

From earlier pattern (cars/cats race):

One promise resolves the fastest with " Car 2 completed " (or analogous " Cat 2 completes " ).

Promise.race resolves with the first settled promise’s value.

In .then, value is " Car 2 completed " and:

let result = `${value} the race.`;

// " Car 2 completed the race. "

Thus result is " Car 2 completed the race. " → option A.