Which of the following can be inferred from this paragraph?

The passage implies that Maria had "made up her mind" to leave the mines to follow her dreams. Note that we cannot yet state if she had started her studies. Likewise, although it might be tempting to say that she merely "went back to school," this really is not all that implied by the passage. Clearly, the paragraph intends to express that she has decided to go back to school to study philosophy. This is a safe assumption, given the details. Likewise, we cannot say anything about how much money she had made in the mines. She might have left the hard work because she was now well-placed financially; however, she might have decided to leave because she was tired of the hard labor.