Final answer:
Forams composed of calcium carbonate can be found above the CCD and dissolve below the CCD due to the deep ocean conditions.
Step-by-step explanation:
Above the CCD (Calcite Compensation Depth), forams composed of calcium carbonate can be found. These forams are marine organisms whose shells are made of calcium carbonate. Below the CCD, the calcium carbonate shells of forams dissolve due to the increased pressure, lower temperature, and higher acidity in the deep ocean.