Which is one way that sinkholes can form? a)rainwater flows away from a depression in the ground. b)tornadoes touch down and destroy trees and brush. c)groundwater dissolves the limestone and other rocks in the ground. d)rivers overflow during a storm and wash away nearby land.

The answer is "C)groundwater dissolves the limestone and other rocks in the ground".

A sinkhole is basically any hole in the ground made by disintegration and the drainage of water. They can be only a couple of feet crosswise over or sufficiently expansive to gulp down structures. In spite of the fact that they're frequently the consequence of characteristic procedures they can likewise be activated by human action.  

Sinkholes may catch surface seepage from running or standing water, yet may likewise frame in without a friend in the world places in explicit areas. Sinkholes that catch waste can hold it in vast limestone caves. These caverns may deplete into tributaries of bigger streams.