Advantage-extra work\data to compare first data with.
Disadvantage-Your data might change over time.
The answer is going to be weathering
I would put option A.
The question says how the surface MIGHT change over a long period of time so that's why I wouldn't say option C, and that's how canyons are formed if I'm not mistaken.
I hope this helps. My apologies if I'm wrong.
Fundamental principle is the answer to the question
