What Prevents the Fetus from Experiencing a Sense of Smell

What prevents the fetus from experiencing a sense of smell?

A) The nostrils are plugged with skin cells and then filled with amniotic fluid.
B) The brain is not developed enough to detect odors.
C) There is no sense of smell without a sense of taste.
D) The sense of smell requires cognitive interpretation which does not take place until 6 months of age.