I think it's C i'm sorry if i'm wrong.
The Sun's increase in activity.
Answer: Principle of Superposition
Explanation: In an otherwise undisturbed sequence of sedimentary strata, or rock layers, the layers on the bottom are the oldest and layers above them are younger. Principle of Original Horizontality: Layers of rocks deposited from above, such as sediments and lava flows, are originally laid down horizontally. Hope this helps!
The andwer is pacific ocean
C.TO DETERMINE the political ideologies of the individuals who live in a country