The last one ("Peter is proud that he uses his brains rather than his brawn, and he would rather go hungry than settle for a manual labor job") is correct.
Explanation:
"had missed many a meal rather than descend in the social scale" suggests that he thinks highly of himself and lowly of manual labor. He holds himself on higher standards and the previous sentences clarify his priortiizing of brains over brawn.
The daughter wished she could have her mother's courage more than anything else her mother had. The brooch was a nice treasure, but she admired her mother's courage more than any object.