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 Input:
Angiosperms inhabit all ____ continents, as well as the oceans.\Question: Choose the right answer from options given a) five b) seven c) three d) zero

Ex Output:
b


Ex Input:
Some homeopathic remedies are so dilute, ____ molecules of the healing substance remain.\Question: Choose the right answer from options given a) ten b) three c) one d) no

Ex Output:
d


Ex Input:
Biceps have ____ heads, triceps have three.\Question: Choose the right answer from options given a) three b) no c) four d) two

Ex Output:

d