A Woman Takes a Combination Birth Control Pill Faithfully

A woman takes a combination birth control pill faithfully. However, she forgets to start her next cycle of pills until four days after the intended start date. The chances that coitus during these four days and several subsequent days will result in pregnancy are

A) low, because she has missed less than a week's worth of pills.
B) high, because her endometrium will be prepared for pregnancy.
C) high, because she may have ovulated in the four days without pills.
D) low, because follicle development is suppressed until the next pill cycle.
E) almost nonexistent, because she took the pill correctly throughout the last cycle.