Reading comprehension is, by definition, the ability to understand words and sentences. I assume that this is just a practice test and you need help interpreting this type of writing.
There is an unspoken circumstance here. The writer assumes that the reader knows about a conflict between two groups, preservationists and restorationists.
Preservationism is obviously some sort of movement supporting the preservation of something. That is, leaving it in its current condition without any interference.
Restorationism is a movement supporting the use of human industry to return of that thing to its original condition.
Preservationists think that the efforts of the Restorationists will destroy, devalue or harm the thing to be preserved, and that a pure "hands off" attitude is the only natural way to care for the thing.
Restorationists think that man is part of nature, and if they actively try to restore the thing, that too will be the natural way.