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').

Q: Human malaria is caused by ____ species of Plasmodium . .\Question: Choose the right answer from options given a) six b) ten c) seven d) four

A: d
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Q: Electrons have almost ____ mass and are negatively charged.\Question: Choose the right answer from options given a) three b) seven c) zero d) no

A: d
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Q: Wings are supposed to have evolved in at least ____ different groups as analogous structures.\Question: Choose the right answer from options given a) no b) five c) ten d) four

A:
d
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