Sinkholes can for when:
A. <span>Rainwater containing carbon dioxide dissolves underground rock
</span>Water in an underground rock<span> or sediment layer is groundwater. </span>Underground<span> water </span>can<span> also erode and deposit material. </span>Rainwater<span> absorbs </span>carbon dioxide<span> (</span><span>CO2) as it falls. The CO2 groundwater creates landforms by </span>dissolving<span> away </span><span>rock.</span>
The Pleistocene often colloquially referred to as the Ice Age) is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the world's most recent period of repeated glaciations. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology.
C. a delta. Because a delta is the only one of those choices to where it is formed at the mouth of a river
