Question: What country are both Yiyang and Chongzuo located in?

Context paragraphs:
Chongzuo: Chóngzuǒ (; Zhuang: Cungzcoj ) is a prefecture-level city in the south of Guangxi Zhuang Autonomous Region along the Sino-Vietnamese border.  It is home to one of China's largest Zhuang populations.

Yiyang: Yiyang () is a prefecture-level city on the Zi River in Hunan province, People's Republic of China, straddling Lake Dongting and bordering Hubei to the north.  According to the 2010 Census, Yiyang has a population of 4,313,084 inhabitants residing in an area of 12,144 km2 .  The previous census was in 2000 when it was recorded there were 4,309,143 inhabitants.

Supporting paragraphs: Yiyang Chongzuo
Answer: China