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').

Metals often crystallize in a ____ dimensional version of the hexagonal closest packed structure.\Question: Choose the right answer from options given a) one b) seven c) three d) eight
c

Toucanets encompass ____ genera.\Question: Choose the right answer from options given a) seven b) six c) two d) one
c

Suckers usually have ten or more comb-like pharyngeal teeth, ____ row on each pharyngeal arch.\Question: Choose the right answer from options given a) two b) five c) one d) zero

c