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: Atoms are extremely small, on the order of a few ____ billionths of a meter.\Question: Choose the right answer from options given a) ten b) seven c) nine d) eight

SOLUTION: a

PROBLEM: Heat pumps give off ____ fumes or harmful products of combustion.\Question: Choose the right answer from options given a) four b) zero c) six d) no

SOLUTION: d

PROBLEM: Hypersensitivity develops over a period of two to ____ weeks.\Question: Choose the right answer from options given a) eight b) zero c) ten d) two

SOLUTION:
c