How does Sitecore utilize dependency injection?

Sitecore uses dependency injection primarily to manage class dependencies effectively. This design pattern allows for the inversion of control, which means that instead of classes directly instantiating their dependencies, they receive them from an external source. This leads to a cleaner architecture, where components are less dependent on concrete implementations, making it easier to modify or replace them without altering the classes that use them.

By leveraging dependency injection, Sitecore promotes more maintainable and testable code. Developers can easily substitute mock objects during testing, enabling unit tests to run more efficiently by isolating components. Additionally, this pattern aids in achieving better separation of concerns—each class only needs to know about the interfaces it works with, not the specific implementations.

The other options relate to outcomes not directly associated with the core purpose of dependency injection within Sitecore. For instance, page load speed, while important, is not a direct consequence of how dependencies are managed. Improving visual layouts pertains to front-end design and presentation, which is distinct from backend architectural practices like dependency injection. Tight coupling of components, in contrast, is something dependency injection aims to avoid, as it seeks to encourage more loosely coupled architecture.