An oppositive does not function like an adverb in a given sentence.
The correct answer is B. <span>what Don Quixote thinks are giants are not really giants.
Sancho Panza is constantly reminding his delusional master about the fact that he is a bit crazy and seeing things that are not actually there. What Don Quixote sees as giants are actually windmills - however, he is completely lost in his world of knights and valor that he cannot see what is actually in front of him.
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