Question

former volcanoes now under the sea are called ______.
submarine shields
cinder cones
seamounts
andesites

Explanation:

Seamounts are former volcanoes that are now underwater. Submarine shields are a type of volcanic formation but not the general term for underwater - former volcanoes. Cinder cones are a type of volcano on land. Andesites are a type of volcanic rock.

Answer:

C. seamounts