Can you provide the passage, as the question is based on it.
Answer:
Doodle is just happy to be with his brother, and that his brother is taking interest in him. Even though his brother is actually ashamed to be seen with Doodle.
Explanation:
The correct answer is d as in dog
(The song's tune is described in the novel as sounding like a combination of "La Cucaracha" and "Oh My Darling)