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').

[Q]: Scorpions also have ____ legs.\Question: Choose the right answer from options given a) eight b) zero c) nine d) ten
[A]: a


[Q]: Potassium helps maintain fluid regulation and normal pH. All ____ help normalize.\Question: Choose the right answer from options given a) three b) six c) two d) one
[A]: a


[Q]: Hatchlings fall into ____ main categories, nidicolous and nidifugous.\Question: Choose the right answer from options given a) nine b) zero c) one d) two
[A]:
d