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]: Harbor porpoises live in groups averaging one to ____ individuals and are very skittish.\Question: Choose the right answer from options given a) seven b) five c) two d) three
[EX A]: d

[EX Q]: Stringers consist of ____ narrow pieces of wood glued together.\Question: Choose the right answer from options given a) ten b) three c) five d) seven
[EX A]: b

[EX Q]: Sea cucumbers have between ____ and thirty such tentacles, depending on the species.\Question: Choose the right answer from options given a) ten b) eight c) zero d) two
[EX A]:
a