instruction:
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').
question:
Echinoderms usually have ____ appendages, but there are some exceptions.\Question: Choose the right answer from options given a) ten b) five c) seven d) three
answer:
b


question:
Reverse osmosis uses ____ to ten gallons of water to produce one gallon of drinking water.\Question: Choose the right answer from options given a) two b) zero c) five d) three
answer:
d


question:
Chemists use one or ____ lettters to represent elements.\Question: Choose the right answer from options given a) seven b) nine c) five d) two
answer:

d