I’ve already done AP’s Phys1, Chem, and Bio.
If I want to apply for a top college in a bio-related major, will not taking a science class look bad?
If there is nothing left to take at your high school, then there is nothing left to take and your counselor can cover that in his/her letter. What aspect of biology are you interested in? If there is an environmental science or anatomy or forensic science or experimental-based psychology class, then you could pick up one of those.
AP physics 2?
Though having all three of biology, chemistry, and physics at the AP level still looks good in any case, even if you do not take a fourth year of science.