Which river rises in China, flows through Laos and Vietnam, and discharges into the South China Sea?
Correct answer: Mekong River

Republic of China
The Mekong River is one of the world's great rivers. Covering a distance of nearly 5,000 km from its source on the Tibetan Plateau in China to the Mekong Delta, the river flows through six countries: China, Myanmar, Thailand, Lao PDR, Cambodia and Viet Nam.