What is a key feature of HackerRank that aids in coding practice?

A key feature of HackerRank that aids in coding practice is its interactive coding environment. This feature allows users to write, test, and debug their code in real-time. The environment provides immediate feedback on code submissions, which is essential for learning and improving coding skills. Users can practice with a variety of coding challenges across different domains and difficulty levels, enhancing their problem-solving abilities.

By facilitating instant code execution and showcasing the results immediately, the interactive coding environment helps learners grasp concepts more effectively. This hands-on approach is crucial for users to solidify their understanding and become proficient in programming.

The other options, while they may enhance the learning experience on their own, do not focus directly on the core coding practice functionality that HackerRank is designed for. For example, mock interviews provide valuable real-world interview practice, and video tutorials offer instructional content, but the interactive coding environment specifically emphasizes coding proficiency through direct engagement.