65. How do the estrous and menstrual cycles compare?
(A) Endometrial bleeding occurs during the menstrual cycle; the endometrium is reabsorbed by the uterus during theestrous cycle.
(B) There are more pronounced behavioral changes during menstrual cycles than during estrous cycles.
(C) There are stronger effects of season and climate on menstrual cycles.
(D) Copulation can only occur during the period surrounding ovulation in both the estrous and menstrual cycles.
(E) The length of both cycles averages 28 days.