Respuesta :
The correct answer is: The echoing sound of his voice shows his excitement that his brother is communicating. The text shows the desperation of the narrator not knowing if his brother was actually able to communicate, he probably wondered if he had a soul at all. He even thinks of killing him at some point because of that desperation. However, when he sees him smile, he gains hope again and realizes with excitement he still has a soul and is capable of doing the same things he does, the same things a person does.
The answer is B. The narrator confesses that even more difficult than having an invalid brother was the fact that he couldn't receive any response from him, he thought that it was impossible to interact with his brother. But, to his surprise, he was proved wrong, by seeing his brother's reaction, which moved him to run and shout to give his mother the good news.