Answer:
The correct answer is - the principle of uniformitarianism.
Explanation:
The principle of uniformitarianism is the principle that helps in understanding the history of the earth. This concept developed by James Hutton has an idea that Earth has always changed in uniform ways and that the present is the key to the past.
According to this theory, the earth is always a geological process that developing as it was developed or change in past in a uniform manner. It is one of the fundamental principle.