Xiao and Feng Have a Fun Sex Life

Xiao and Feng have a fun sex life. They care for each other and are frequently trying new things, although they have been together so long they are not as attracted to each other as they once were. Last year Feng had a casual sexual encounter that Xiao later found out about, but she decided to stay in the relationship. According to Peggy Kleinplatz's research, what may be a barrier to optimal sexual pleasure for Xiao?

A) Low arousal
B) Resentment
C) Lack of attraction
D) Trust