By repeating certain words he says back to him
John H. Watson, known as Dr. Watson, is a fictional character in the Sherlock Holmes stories by Sir Arthur Conan Doyle. Watson is Sherlock Holmes' friend, assistant and sometime flatmate, and the first person narrator of all but four of these stories.
Answer:
Amir has a rich background while Hassan has a poor background.
Explanation:
The descriptions of Amir's possessions are those of a person who is rich. He has a magnificent house and he has a red brick driveway which also suggests that he also owns cars. This implies that he must be rich or that he must come from a rich family because it is only a rich person that can afford to own these things.
Hassan on the other walks towards a little mud hut which also implies that he must come from a poor and humble background.
C. It killed nearly 80% of the population