Answer:
The west and north of the country are dominated by sunken basins (such as the Gobi and the Taklamakan), rolling plateaus, and towering massifs. It contains part of the highest tableland on earth, the Tibetan Plateau, and has much lower agricultural potential and population.
Its territory includes mountains, high plateaus, sandy deserts, and dense forests. One-third of China's land area is made up of mountains. The tallest mountain on Earth, Mount Everest, sits on the border between China and Nepal. China has thousands of rivers.
Mountains, deserts, rivers, beaches, deep canyons and fertile plains all make up China's unique and storied geography.
The vast land expanses of China include plateaus, plains, basins, foothills, and mountains. Defining rugged plateaus, foothills and mountains as mountainous, they occupy nearly two-thirds of the land, higher in the West and lower in the East like a three-step ladder.
The correct answer is - (1) velocity of the river decreases.
When the velocity (the speed) of the river decreases, be it at the entry of a lake, sea, ocean, or meandering, passing through a valley with very little change in altitude, the sediment starts to get deposited. This is due to the decrease in force caused by the decrease in velocity, there is not enough force to push the sediments further so they start to deposit because the river is not able to drag them further on.
