Answer is C = Speaker
How? as the speaker is the only item on the list that displays any type of content, that being audio, it's the only feasible answer to this question.
Answer:
D. Low-level components are combined into clusters that perform a specific software sub-function
Explanation:
Normally, regression testing are done on a manual basis by simply re-executing a subset of the entire available test cases or it can be done automatically by utilizing playback tools or automated capture. Hence, from the options, a combination of low-level components into clusters that perform a specific sub-function does not align with how regression testing are done either manually or automatically.
It helps reveal the flow of execution of your program, including results of in-between evaluations. In other words, you can see what your program is doing, and why it takes the decisions it is taking.
If something unexpected happens, the trace will show you the sequence of events that lead to it.