China's four geographical regions, with traditional local houses, are large, not northern Shaanxi.

As can be seen from the diagram, Mountain C is the Qinling Mountains, with the south area in the south and the north area in the north.

Combination options: Beijing quadrangles and caves in northern Shaanxi are traditional houses in the northern region; Mongolian yurts in Inner Mongolia are traditional houses in northwest China. Fujian is located in the south of China, and Fujian Tulou is one of the traditional houses in the south. Combination options.

So choose: C.