<p>Ms. Baldwin was nominated as Best New Painter <u>for</u> her elaborate painting now on display at Richmond Gallery.</p>
<div data-answer="c">(A) about - Incorrect. "About" does not make sense in this context. The preposition "about" is used to indicate a general or approximate time or place, or to express the subject or object of a discussion or consideration. However, in this sentence, we are talking about the reason for Ms. Baldwin's nomination, not a general or approximate time or place.</div>
<div data-answer="c">(B) when - Incorrect. "When" is used to indicate a specific time or event. However, in this sentence, we are talking about the reason for Ms. Baldwin's nomination, not a specific time or event.</div>
<div data-answer="c">(C) for - Correct. The preposition "for" is used to indicate the reason or purpose for something. In this sentence, Ms. Baldwin was nominated as Best New Painter because of her elaborate painting.</div>
<div data-answer="c">(D) since - Incorrect. "Since" is used to indicate a specific point in time or a period of time starting from a specific point. However, in this sentence, we are not talking about a specific point in time or a period of time starting from a specific point.</div>