The mountain ranges and rivers in Southeast Asia have made a stripe like relief in the mainland of this region. The mountain ranges are in a north-south direction and separate the region into few big elongated valleys, and the 5 big rivers also are moving from the north towards the south (southeast, southwest as well), and are running in between the mountain ranges and cut through the valleys.
<span>B. they needed access to bodies of water for trade
Water and aquatic access was necessary for water as well as access to trade.
Hope this helps :)</span>
Answer: climate change
Explanation: less rain means less water for consumption.
uplift-weathering-erosion-subsidence
