Answer:
d. Bathymetry
Step-by-step explanation:
Bathymetry is the study and mapping of the ocean floor and the topographic and relief features found there. On a bathymetric map we can see undersea mountain ranges, trenches, gradually rising sea mounts, underwater plains, continental shelves and many other types of undersea features. These maps were traditionally made using sonar technology installed on boats, but they can also be obtained using satellites using microwave measurements that are much more precise.