Question

rocks in ocean crust are as old as ______ years.
a. 200 million
b. 4.4 billion
c. 44 million

Explanation:

The oceanic crust is constantly being recycled at subduction zones. The oldest oceanic crust is about 200 million years old. Continental crust can be much older (up to 4.4 billion years in some cases), but the question is about ocean crust. 44 million is too young for the oldest ocean crust.

Answer:

A. 200 million