Answer:
B. Write down your test grades after each test and compare them.
Step-by-step explanation:
A teacher cannot fully understand each of their students, so asking them directly about one's strenghts might not be a satisfactory idea in most cases.
Instead, one as a student can directly take tests and compare results between each one done. This method will provide feedback regarding what areas one seems more proficient at, as well as which require extra effort.