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]: Reservoirs cover an area of the planet ____ times the size of Britain.\Question: Choose the right answer from options given a) two b) eight c) three d) six
[EX A]: d

[EX Q]: China is reportedly in the top ____ nations in industrial output.\Question: Choose the right answer from options given a) seven b) ten c) three d) five
[EX A]: b

[EX Q]: Acoustic instruments consist of ____ main parts neck, top, back and sides.\Question: Choose the right answer from options given a) eight b) four c) one d) seven
[EX A]:
b