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: Young emus are very vulnerable to disease until they are about ____ months old.\Question: Choose the right answer from options given a) no b) ten c) six d) three

A: d
****
Q: Golden jackals live eight to ____ years in the wild and up to sixteen in captivity.\Question: Choose the right answer from options given a) no b) zero c) ten d) nine

A: d
****
Q: Cranes mate for life and often pair when they are ____ to six years old.\Question: Choose the right answer from options given a) three b) four c) one d) seven

A:
a
****