Which of the following best describes validation in software engineering?

Validation in software engineering focuses on ensuring that the system meets the needs and expectations of the customer. It is about checking whether the final product delivers the functionalities and qualities that the customer requires, confirming that the right product has been built according to the user's requirements. This process typically involves different levels of testing, including user acceptance testing, where actual users evaluate the software against their needs.

In contrast, the other options describe different aspects of the software development life cycle. For example, ensuring the system meets technical specifications is related to verification rather than validation; it deals more with confirming that the system is built correctly according to defined specifications. Testing for software bugs and errors also pertains to finding issues within the software but does not directly assess whether the software meets user expectations. Completing documentation is an essential part of project management, ensuring that records are up to date, but it does not pertain to the validation of the software itself. Thus, the focus of validation on customer satisfaction makes it the correct answer.