GMAT Critical Reasoning (CR) | Re: The Earth s rivers constantly carry dissolved salts into its

Option B would not be correct because it is not necessary that all the rivers of the earth have about the same salt levels at any given time. They can actually have different salt levels. In other words, it is possible that the salt level of one river is different from the salt level of another river.

When I closely think about it, I believe that possible assumption could have been that rivers have actually been carrying approximately the same “quantity”
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