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]: Parliaments can last five years, often last ____ and a bit.\Question: Choose the right answer from options given a) four b) three c) five d) two
[EX A]: a

[EX Q]: Cows breed at ____ years, bulls at four.\Question: Choose the right answer from options given a) two b) three c) seven d) one
[EX A]: b

[EX Q]: Ribosomes are small, irregularly shaped particles, composed of ____ subunits.\Question: Choose the right answer from options given a) two b) eight c) three d) seven
[EX A]:
a