19. At birth, the ovaries contain around 1-2 million primary oocytes, of which about 500 fully mature from puberty to menopause. When do these germ cells complete meiosis II?
(A) at birth
(B) at puberty
(C) during copulation
(D) after fertilization by sperm
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統計: A(0), B(2), C(0), D(6), E(0) #3839954
統計: A(0), B(2), C(0), D(6), E(0) #3839954