Virus since it’s a strain of flu
Answer:
Mutations happen in our cells all the time. It's actually how all humans grow and change. The vast majority of mutations are harmless. Thus, they aren't avoidable.
Since the cell is hypotonic compared to the solution surrounding it which is hypertonic, the water will move out of the cell in an effort to reach equilibrium between the two.
I believe the answer would be B, provide support for a weakened joint. I don't think braces could protect you from big impacts, and I'm sure it's not just to keep your arm cool.