The rest operator (...) is used in function parameters to collect all remaining arguments into an array. In the example function myFunction(a, b, ...rest), the ...rest collects any additional arguments passed to the function into an array named rest.

To make the properties of an object immutable in JavaScript, you can use the Object.freeze() method. This method prevents any changes to the object's properties, making them read-only. The other options, Object.preventExtensions() and Object.seal(), allow some level of modification but not full immutability, and Object.makeImmutable() is not a valid method in JavaScript.

When creating a multidimensional array in JavaScript, each element of the main array is a reference to another array or value. This allows for the creation of nested arrays. Changes made to the referenced arrays will affect the main array.

In JavaScript, you can use a while loop to execute a block of code repeatedly as long as a specified condition is true. The for loop is used for iterating over a sequence, and if and switch statements are conditional constructs, not loops.

To schedule a specific action immediately after the current operation completes, you should use process.setImmediate(() => { /* Action code */ });. This ensures that the action is placed in the event queue and executed as soon as possible after the current operation. The other options do not serve this purpose correctly.

In Express.js, static files typically include images, CSS files, and JavaScript files. These files do not change dynamically and can be served directly to clients. HTML files are often dynamically generated, and configuration files are not typically served as static files.

The commonly used configuration file for ESLint is .eslintrc.json. This file allows you to specify ESLint rules, plugins, and other configuration options for your project.

The GET HTTP method is used for reading data in CRUD (Create, Read, Update, Delete) operations. It retrieves data from the server without making any modifications.

The primary purpose of the NPM (Node Package Manager) registry in Node.js development is to host and distribute Node.js packages and modules. It serves as a centralized repository for sharing and discovering reusable code, making it a crucial component of the Node.js ecosystem. Option 1 is incorrect because NPM is not used to install Node.js itself; you would use a Node.js installer for that. Option 2 is incorrect because NPM primarily manages packages on a project-specific level, not globally. Option 4 is incorrect because the NPM registry is not used to execute JavaScript code directly.

The Time-To-Live (TTL) value in caching determines how long the data should remain in the cache before being expired. When data expires, it is removed from the cache and, if needed, can be fetched again from the source.