What is the best practice to apply in your code to improve the performance of your application?

Question

In the development of a Node.js e-commerce web application with HTML pages of more than 1mo you are looking to optimize performance to handle high traffic and provide a fast user experience. 
Your server is at 60% of its maximum capacity at peak times.

What are the two best practices to apply to achieve this goal? (Choose two answers)

Accepted Answer

Enable gzip compression for HTTP responses, thus reducing the amount of data transmitted when loading web pages

Accepted Answer

Use asynchronous functions instead of synchronous functions, to avoid blocking the main thread when querying a database

Answer

Handle exceptions correctly to avoid application crashes

Answer

Increase the number of worker threads to improve task parallelism

Question from the Node.js - Fundamentals test

What is the best practice to apply in your code to improve the performance of your application?