In a top-down development strategy, which level of testing is mainly affected?

In a top-down development strategy, integration testing is primarily affected because this approach begins testing at the highest level of the application first. In this strategy, major components or modules are developed one at a time, starting from the top-level module and progressively developing lower-level modules.

During the integration testing phase, higher-level components are integrated and tested even when some lower-level components are not fully developed. To facilitate testing at this stage, stub programs may be used to simulate the behavior of the lower modules that are still under development. Thus, integration testing is crucial since it focuses on combining and verifying the interactions between these integrated components.

In contrast, component testing focuses on the individual functionalities of lower-level components, which may not be fully developed at the initial stages of top-down development, making it less impacted at this point. System testing occurs after integration testing and assesses the entire system's compliance with specified requirements, while user acceptance testing is conducted at the end of the development process to verify that the system meets user needs. Therefore, integration testing is the level that is most directly affected by the top-down development approach.