The person who suggested that the continents were once a supercontinent, called Pangaea, but slowly drifted apart was Albert Einstein Alfred Wegener Isaac Newton Harry Hess

The correct answer is: Alfred Wegener. Alfred Wegener (1880-1930) was a German polar researcher, meteorologist and geophysicist, and a first person who suggested that the continents were once a supercontinent called Pangaea, but slowly drifted apart. While he was still alive, Wegener was best-known for his achievements in meteorology and as a pioneer of polar research, but today he is most remembered as the creator of the theory of the continental drift. This idea was controversial in the beginning, but today, scientist believe that Pangaea really existed during the late Paleozoic and early Mesozoic eras.