Answer:
A reader should stop after the second sentence and ask, "What does Armenian and Turkish music sound like?"
Step-by-step explanation:
In the given excerpt, the narrator remembers how his mother would play music "in the summertime [with the] windows open". And this would bring comments such as "foreigners" from his friends who wouldn't understand what the music was.
Likewise, we, the readers can most understand the mother's love of music by asking the question of what exactly does Armenian and Turkish music sound like. So, asking this question right after the second sentence will best help us understand the mother's love for music.
Thus, the correct answer is the third option.