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: All spider mites have ____ legs and a lack of a separate head.\Question: Choose the right answer from options given a) eight b) four c) ten d) one

Answer: a


Question: Humans learn through the ____ senses.\Question: Choose the right answer from options given a) eight b) one c) five d) ten

Answer: c


Question: Neutrinos do exist, in huge numbers, but all known neutrinos have ____ mass.\Question: Choose the right answer from options given a) eight b) zero c) one d) four

Answer:
b