<span>A. Ocean currents, is the only logical answer this question I mean come on I know for a fact I'm correct</span>
Answer:
measuring seismic wave activity
Explanation:
the earths interior is made up of a number of layers such qs the crust, mantle, outer and inner cores.
The river had been called <span>"river of sorrows" due to its constant flooding during its earlier civilizations. </span>
I think is Asia, but I could be wrong
(but it probably is so yei)
