Answer:
B. Karst regions and carbonate rock outcrops occur on every continent except Antarctica.
Explanation:
Karst is an area made up of limestone. Antarctica's geology make its more complicated for this outcrops occurance, there are several karst regions all over the world such as:
Ankarana Reserve, Madagascar (Africa)
South China Karst, World Heritage Site (Asia)
South Harz and Kyffhaeuser Gypsum Karst, Germany (Europe)
Illinois Caverns State Natural Area and Illinois Sinkhole Plain in Monroe County (North America)
Los Haitises National Park, Dominican Republic (Central America)
The Sierra de San Luis in Falcón State, Venezuela (South America)
Jenolan Caves, New South Wales (Oceania)