The best answer for this question would be:
D. That he feels like a failure as a man
On the given text the emotions that Walter puts explains how
he feels about himself, stating that “So you butchered up a dream of
mine—you—who always talking 'bout your children's dreams”
"Come," I said, with decision, "we will go back; your health is precious. You are rich, respected, admired, beloved; you are happy, as once I was. You are a man to be missed. For me it is no matter.
You could talk about the great depression.
Scout characterizes Boo as a petty criminal and a "malevolent phantom." Jem describes his neighbor as a monstrous figure, six-and-a-half feet tall with bloodstained hands. Dill must imagine Boo based on the descriptions his friends provide him.