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: Sea stars have ____ arms, or rays, connected to a small round body.\Question: Choose the right answer from options given a) five b) six c) seven d) no

SOLUTION: a

PROBLEM: Many animals use two or ____ forest structure types.\Question: Choose the right answer from options given a) eight b) zero c) two d) three

SOLUTION: d

PROBLEM: Some species have vestigial tails or ____ tails at all.\Question: Choose the right answer from options given a) eight b) nine c) no d) three

SOLUTION:
c