You didn't show the answer choices. You could have just taken a photo or something.
<span>Persia would be the most likely location. With Merv being in the very center and Persia being right in the middle between Syria and China, Persia is most certainly the most common meeting place for people coming from the far ends of each side of the silk road.</span>
The correct answer is B.
This river is also called the Chang Jiang or Long River
