Answer: b.
His manhood and adventurous spirit
Step-by-step explanation:
This question is referring to the artwork of Virginia Woolf ''Mrs. Dalloway'' in which Peter Walsh is one of the characters and he always had his knife with him in his pocket. The symbol of that knife to him was his manhood and adventurous spirit.
He is one middle-aged mad that sometimes has that feeling like he is too old, and sometimes he thinks that he is not too old for more advenures. He is unpredictable, he does not want to talk about feelings and he is crashing.