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: Government buildings fly flags of the ____ nations.\Question: Choose the right answer from options given a) ten b) no c) seven d) two

SOLUTION: d

PROBLEM: Decapod crustaceans have ____ pairs of limbs.\Question: Choose the right answer from options given a) five b) four c) six d) seven

SOLUTION: a

PROBLEM: Sound waves travel about ____ times as fast in water and about ten times as fast in steel.\Question: Choose the right answer from options given a) four b) three c) seven d) eight

SOLUTION:
a