Females of Most Species Are Willing to Engage in Sex

Females of most species are willing to engage in sex only during their ___ period,whereas female humans and some primates ___.

A) estrus,are not willing to engage in sex except outside their estrus cycle
B) menstrual,are willing to engage in sex anytime during their estrus cycle
C) estrus,are willing to engage in sex anytime during their reproductive cycle
D) menstrual,are only likely to engage in sex during their estrus cycle