Given a sentence with a missing word, pick the answer option that best fills out the missing word in the sentence. Indicate each answer with its index ('a', 'b', 'c', 'd').

Females inherit ____ X chromosomes, one from each parent.\Question: Choose the right answer from options given a) five b) two c) no d) seven
b

Women gain ____ years per child they had.\Question: Choose the right answer from options given a) ten b) nine c) four d) two
d

Pathologists study ____ to five years after medical school and their postgraduate training.\Question: Choose the right answer from options given a) two b) zero c) four d) ten

c