How Is the Merging of Continents to Form Pangaea Believed

How is the merging of continents to form Pangaea believed to have altered Earth's environments at the end of the Paleozoic era?

A) Shallow coastal areas were drained,leading to the extinction of many marine species.
B) It eliminated all multicellular eukaryotes,allowing evolution to start anew.
C) It made the climate warmer and moister for terrestrial organisms in the center of the new land mass.
D) It prompted an immediate increase in Earth's biodiversity.