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').
--------
Question: Today there are ____ UK hospitals doing heart transplants.\Question: Choose the right answer from options given a) three b) five c) six d) nine

Answer: d


Question: Batteries consist of ____ electrodes immersed in an electrolyte.\Question: Choose the right answer from options given a) two b) eight c) three d) seven

Answer: a


Question: Biennials complete their lifecycles in less than ____ years.\Question: Choose the right answer from options given a) five b) two c) eight d) ten

Answer:
b