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').

[EX Q]: Worker bees have ____ pairs of wax glands on the underside of their abdomens.\Question: Choose the right answer from options given a) no b) two c) nine d) four
[EX A]: d

[EX Q]: Hummingbirds feed every ____ to fifteen minutes from sun-up to sundown.\Question: Choose the right answer from options given a) nine b) seven c) four d) ten
[EX A]: d

[EX Q]: Colds tend to last ____ to ten days, while allergies can go on for weeks.\Question: Choose the right answer from options given a) ten b) nine c) zero d) seven
[EX A]:
d