Answer:
Africa
Step-by-step explanation:
The four hemispheres are separated by the equator, separating the North and South hemisphere, and the prime meridian, separating the eastern and western hemispheres.
As the prime meridian (0 degrees longitude) passes through the continent of Africa, Africa can be said to occupy land in both of these hemispheres. The equator (0 degrees latitude) also passes through the continent of Africa, so Africa also occupies land in these two hemispheres as well.