Answer: 'A' is the response.
Explanation: The diagram A appears to show a location where magma is rising as a result of an upwelling convection current in the magma, which could cause the sea bottom to spread. The spreading of the crust is indicated by the arrows. This will become a focal point for the spreading marine floor.
To learn more about oceanic spreading center refer:
brainly.com/question/13892552
#SPJ2
Superposition is the geologic principle which explains why the bottom stratum in a section of rock is the oldest. The word literally means placing one thing on top of another where the lower strata are the older.