TASK DEFINITION: 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').
PROBLEM: Cats have ____ sets of vocal cords.\Question: Choose the right answer from options given a) zero b) nine c) two d) three

SOLUTION: c

PROBLEM: Angiosperms inhabit all ____ continents, as well as the oceans.\Question: Choose the right answer from options given a) five b) seven c) three d) zero

SOLUTION: b

PROBLEM: Sirenians are solitary, travel in pairs, or associate in groups of ____ to about six individuals.\Question: Choose the right answer from options given a) three b) no c) one d) two

SOLUTION:
a