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').

Conflict diamonds account for less than ____ per cent of world trade in rough diamonds.\Question: Choose the right answer from options given a) two b) four c) one d) ten
b

Every person is a carrier for about ____ rare genetic conditions.\Question: Choose the right answer from options given a) nine b) ten c) six d) three
b

Poles CAN occur at ____ frequency.\Question: Choose the right answer from options given a) six b) four c) zero d) eight

c