Question

based on the map, which statement is correct?
the ocean floor found at site 21 and site 16 are the same age.
site 16 has the oldest ocean floor, because it is closer to the mid - atlantic ridge.
site 21 has the youngest ocean floor, because it is farther from the mid - atlantic ridge.
site 21 has the oldest ocean floor, because it is farther from the mid - atlantic ridge.

Explanation:

The Mid - Atlantic Ridge is a divergent plate boundary where new oceanic crust is formed. The farther a site is from the ridge, the older the ocean floor. Site 21 is farther from the Mid - Atlantic Ridge compared to other sites shown, so it has the oldest ocean floor.

Answer:

Site 21 has the oldest ocean floor, because it is farther from the Mid - Atlantic Ridge.