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]: Black widows mature in ____ to four months.\Question: Choose the right answer from options given a) two b) seven c) eight d) zero
[A]: a


[Q]: Pupae usually transform into adults ____ to three days later.\Question: Choose the right answer from options given a) one b) two c) no d) eight
[A]: b


[Q]: Compounds consist of ____ or more elements in fixed proportions.\Question: Choose the right answer from options given a) three b) ten c) two d) nine
[A]:
c