Which statement about the rock fossils is true?

fossil y is older than fossil x.
fossil z is younger than fossil y.
fossil z existed over many periods of time.
fossil y existed during the same period as the ammonite.

Option (2)

Explanation:

In the given figure, fossil X is the oldest fossil as it is present at the base of the rock formation. above this layer, is the rock layer that contains the fossil Y and it forms the middle layer.

The topmost layer is the rock layer that contains the fossil Z and some ammonites are also present. This layer is the youngest layer.

So from all the above data, we can conclude that fossil Z is younger than fossil Y as well as fossil X.

Thus, the correct answer is option (2).