Answer: A )to illustrate Japan’s isolation in the 1800s
The author starts the paragraph by telling us that Japan was isolated during the 1800s. He goes on to introduce an outside source (Stephen Sondheim's musical tableau) as a way to back up this assertion. Although this might seem unnecessary, his reason for including it is to illustrate Japan's isolation during this time period. The source shows how other countries thought about Japan's situation, and it provides evidence for the author's claim.
