I think it is D because if he was just found he was alone
What can be inferred based on this description is that many East Egg residents<span> hide their unattractive qualities beneath beautiful, light, and dreamy appearances.
As is the case of Daisy and Tom - they live in a beautiful manor which seems perfect on the outside, just like Daisy and Tom do. However, if you take a peak inside, you will see their true selves - they are unhappily married, Tom is cheating on her with Myrtle, and Daisy is cheating on him with Gatsby.
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<span>D) Michelle's paintings stood out vividly when they were displayed against a neutral background.
The subordinate clause is "when they were displayed against a neutral background. Even though part of this clause could stand alone: they were displayed against a neutral background, using the word 'when' makes the clause dependent. We need to know what happened WHEN they were displayed. The rest of the sentence solves this - Michelle's paintings stood out vividly. </span>