I think that it's A, maybe C
Answer is A. D-Trying to fit in is them doing asking you to do it an you do even if you've never done it.C- Feeling as though " everyone is doing it" is alot similar to trying to fit in. B- Wanting to be like is the same thing as trying to fit in just said differently.
The most appropriate answer is D ! as other three are not related to cilia any way !
so D
if you want more info on this, comment !
Genes is the correct answer.
