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:
Copper is ____ times higher in dog liver than in human liver.\Question: Choose the right answer from options given a) three b) ten c) six d) one

Ex Output:
b


Ex Input:
Acoustic guitars come in ____ types.\Question: Choose the right answer from options given a) two b) ten c) one d) four

Ex Output:
a


Ex Input:
Fruit is a silique opening by ____ valves.\Question: Choose the right answer from options given a) ten b) three c) eight d) two

Ex Output:

d