B is the answer as it makes more sense
Answer:
The doctor didn't want them to see how much pain Johnny was in, but because they were his friends (not because of the blade) the doctor decided to let them in anyways.
Answer: C.
This answer choice not only has an engaging tone that "hooks" the reader in, but it is also a strong introductory sentence that gives the reader something to think about and, ultimately, engages them and encourages them to continue reading.