The diagrams below represent two series of rock layers. Each diagram represents the same time interval, which ranges from the Paleocene geologic epoch to the the Miocene geologic epoch. Each rock layer is represented by a unique combination of color and pattern. Each layer is also labeled with the type of environment in which the layer formed. Examine the diagrams, and then answer the question that follows.

Which of the following is true about these diagrams?
A.
Both diagrams represent the same sudden change from a shallow ocean environment to an inland desert environment.
B.
Diagram X represents a more sudden change from a shallow ocean environment to an inland desert environment than does diagram Y.
C.
Diagram X represents a more gradual change from a shallow ocean environment to an inland desert environment than does diagram Y.
D.
Both diagrams represent the same gradual change from a shallow ocean environment to an inland desert environment.