Answer:
C.
Bassanio's decision to choose the lead casket shows that one must not judge things or people by their appearance.
Step-by-step explanation:
The theme of the story is that appearances can be deceptive. In the story, while the two princes choose the gold and the silver caskets, Bassanio chooses the lead casket because he does not value outward beauty. Therefore, "Bassanio's decision to choose the lead casket shows that one must not judge things or people by their appearance."