Several of sheldon's friends suggest that the new girl in their class is very pretty. sheldon does not think that she is pretty. if sheldon is exhibiting conformity, he is probably going to

The correct answer is - agree with his friends and say that she is very pretty.
Sheldon is going to conform to the general opinion - his friends think the new girl is very pretty, and he is going to agree with them because the majority thinks she is pretty. Even though he doesn't think the same way as they do, he is still going to say what they do in order to fit in. 

The repetition of initial consonant sounds is called alliteration