What is the physical pattern formed by the mountain ranges and rivers of mainland southeast asia?

The common physical pattern formed by most of the mountain ranges and rivers of mainland Southeast Asia is that of their orientation and origin in the north.

Explanation:

It is a fact that most mountain ranges in Southeast Asia lie in the north and most rivers flowing in Southeast Asia originate in these mountains. The Himalayas in the northern part of Southeast Asia have been formed as a result of the convergence of two continental plates. These mountains are glaciated and are thus the source of most rivers in the region.

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