By changing the type of obstacle the characters face
Answer: E) My mother considered the idea of a child sleeping alone a cruel American practice.
This sentence shows that the mother had a cultural background that was different from the American one. Even though for most Americans, a child sleeping alone would be common, for her it was a cruel practice. The excerpt shows that Hema's mother does not endorse all American practices, which indicates she has a different cultural heritage, in this case, a Bengali one.
