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').

Insects are arthropods that have a body with three segments, ____ legs, and one set of antennae.\Question: Choose the right answer from options given a) three b) one c) six d) zero
c

Many soils have ____ major layers or horizons, top soil, subsoil and parent material.\Question: Choose the right answer from options given a) one b) two c) seven d) three
d

Anaerobic bacteria are most active over the weekend when ____ processes are running.\Question: Choose the right answer from options given a) seven b) six c) no d) four

c