Even Though It Is Easier to Reach Orgasm Through Masturbation,why

Even though it is easier to reach orgasm through masturbation,why do many heterosexual women report increased pleasure with vaginal intercourse over masturbation? 

A)  Orgasms through vaginal intercourse tend to be more intense. 
B)  Intercourse provides more intimacy and closeness. 
C)  Most women prefer to delay their orgasms as long as possible for heightened pleasure. 
D)  Their partners are more adept at stimulating them than they are themselves.