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').

Tropical trees can be rampant growers, and can outgrow a wiring in as little as ____ days' time.\Question: Choose the right answer from options given a) four b) eight c) six d) ten
d

Females can only have four babies at ____ time.\Question: Choose the right answer from options given a) no b) one c) nine d) three
b

Most juveniles remain in their natal river from ____ to six years before migrating to the ocean.\Question: Choose the right answer from options given a) ten b) eight c) one d) zero
c