Answer: B. Limestone cave collapsing due to changes in sea level.
Step-by-step explanation:
A underwater sinkhole is a hole in the ground that formed when the rocks and soils are removed by the flowing water. A sinkhole forms due to groundwater deposition.
A limestone cave is an example of an underwater sinkhole. It forms when the calcium carbonate or limestone deposits of the underground soil are disrupted by the water from any source like rain, snow melting and sea. This forms a geological feature that is underwater sinkhole.