Answer :
The way caves form in limestone, using evidence from the diagram is A. Chemical weathering
Rainwater dissolves carbon dioxide from the atmosphere, which creates a weak carbonic acid. This acidic water slowly dissolves the limestone, eventually forming caves over millions of years [1].
Rainwater seeps through the soil and picks up carbon dioxide from the atmosphere. The carbon dioxide reacts with the water to form carbonic acid, a weak acid. The carbonic acid slowly dissolves the calcium carbonate in the limestone, which is a soluble rock. Limestone, composed mainly of calcium carbonate, is susceptible to dissolving in weak acids.
