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]: Anthrax usually is a fatal disease with ____ symptoms observed.\Question: Choose the right answer from options given a) no b) seven c) one d) six
[A]: a


[Q]: Elephants have four molars, which are replaced ____ times, for a total of six sets in a lifetime.\Question: Choose the right answer from options given a) five b) no c) three d) one
[A]: a


[Q]: Sexual maturity occurs in females when three or ____ years old and in males at five years.\Question: Choose the right answer from options given a) no b) seven c) one d) four
[A]:
d