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').

[EX Q]: Mechanical digestion occurs as ____ strong layers of muscle contract to produce a churning motion.\Question: Choose the right answer from options given a) four b) no c) three d) six
[EX A]: c

[EX Q]: Control is defined as a dead plant with ____ signs of life.\Question: Choose the right answer from options given a) ten b) nine c) no d) zero
[EX A]: c

[EX Q]: Some families have two daddies or ____ mommies.\Question: Choose the right answer from options given a) nine b) seven c) zero d) two
[EX A]:
d