Answer:
Curtis can use the Option A to keep the research focused.
Option A displays the following question:
How did blues music influence other genres of music in the twentieth century?
We can arrive at this answer because:
A research on the blues should underscore the importance of this genre for the music industry.
In this case, research should focus on this influence, showing how it was established and distributed in other musical genres.
This keeps the reader excited to keep reading.
However, the author of the text must keep the theme of the text well established, without losing focus during the text. For this, this author must answer the question: "How did blues music influence other genres of music in the twentieth century?"