Xiao Ming is very interested in geography. He is going to travel from Chengdu to Harbin, Wuhan, Kunming and Guangzhou in the summer vacation. When he consulted the map, he drew the outlines of the provinces and regions where the four provincial capitals are located, and also drew the largest rivers in each province. Please know according to the geography he has learned.

In the picture, ① Yunnan Province, ② Guangdong Province, ③ Hubei Province and ④ Heilongjiang Province. Guangdong Province is a coastal province with no land neighbors (borders). The Yangtze River originates from Tanggula Mountain, and its main stream flows through 11 provinces and regions including Qinghai, Tibet, Sichuan, Yunnan, Chongqing, Hubei, Hunan, Jiangxi, Anhui, Jiangsu and Shanghai, and finally flows into the East China Sea, with a total length of 6,300 kilometers.

Therefore, choose: B.