Replaced agriculture with factories
<span>Erosion by rivers is a main valley-forming
process; other processes, such as movement of the earth's crust and
glaciers, also have an important part in some cases. The rate at which a
river deepens its valley depends on several factors.</span>
I don't know whether this was one of your options, but South Asia can be very well characterized as a Sub-continent.
In fact, it's is commonly referred to as "the Indian Subcontinent" or even simply "Subcontinent". One of the reason for a distinction of this part of the land is that it lies on a different tectonic plate.
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A two-column proof contains a table with a logical series
of statements and reasons that reach a conclusion. It is commonly present
in geometry. Two column proofs always have two columns: statements and reasons.
The other choices don’t fit in the definition of two column proof.
