Part A: The piece of iron most likely symbolizes C. his father's distrust of white people. This interpretation suggests that the iron, which is associated with white culture and technology, represents a complex relationship with the white community, reflecting Iron Shell's inner conflict and distrust stemming from historical tensions.
Part B: The quotation that most clearly supports the answer to Part A is A. He did not understand his vision of finding something belonging to the white people, for in that time they were the enemy. (paragraph 64). This quotation directly addresses the distrust towards white people and the tension around owning a piece of their culture, thereby reinforcing the symbolic interpretation of the piece of iron.