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').

Onion thrips experience ____ instars.\Question: Choose the right answer from options given a) three b) six c) eight d) four
d

Circles mark the approximate locations of ____ recently discovered solar systems.\Question: Choose the right answer from options given a) four b) no c) zero d) nine
a

Manual power means ____ sparks due to ignition found in gasoline and electric winches.\Question: Choose the right answer from options given a) six b) no c) three d) five

b