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]: Whales are divided into ____ categories, based on their teeth.\Question: Choose the right answer from options given a) two b) four c) nine d) ten
[EX A]: a

[EX Q]: Chlorine is manufactured in ____ ways.\Question: Choose the right answer from options given a) four b) two c) nine d) seven
[EX A]: b

[EX Q]: Lightning can occur as far as ____ miles from where rain is falling.\Question: Choose the right answer from options given a) one b) ten c) two d) five
[EX A]:
b