Which type of testing focuses on the overall behavior and performance of the system?

The correct choice emphasizes system testing, which is designed to validate the complete and integrated software product. This type of testing assesses the system as a whole against specified requirements, focusing on its overall behavior and performance. System testing encompasses functional and non-functional testing, examining how the system responds under various conditions, including load, performance, and security.

In system testing, testers verify that the system meets all defined specifications and business requirements in real-world scenarios, ensuring it behaves as expected when subjected to different kinds of user interactions and operational environments. It acts as a final verification step before the product is released to stakeholders or customers, making it crucial for determining whether the software is ready for production.

Understanding system testing is essential because it highlights the importance of evaluating a system's comprehensive functionality and performance beyond isolated parts of the application, thereby ensuring a robust final product.