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]: Neutrinos are particles with almost ____ mass and no electric charge.\Question: Choose the right answer from options given a) no b) two c) zero d) five
[A]: a


[Q]: Most children have a vocabulary of eight to ____ words, including names, by eighteen months of age.\Question: Choose the right answer from options given a) ten b) one c) seven d) eight
[A]: a


[Q]: Organisms have ____ forms of nucleic acid.\Question: Choose the right answer from options given a) four b) three c) two d) one
[A]:
c