S_N1 Reactions Usually Proceed with ________

S_N1 reactions usually proceed with ________.

A) equal amounts of inversion and retention at the center undergoing substitution
B) slightly more inversion than retention at the center undergoing substitution
C) slightly more retention then inversion at the center undergoing substitution
D) complete inversion at the center undergoing substitution
E) complete retention at the center undergoing substitution