What does the author use in this passage to support the idea that the dam has ruined glen canyon?

This question is incomplete, here´s the complete question.

What does the author use in this passage to support the idea that the dam has ruined Glen Canyon?  

For those who may think I exaggerate the contrast between the former river canyon and the present man-made impoundment, I suggest a trip on Lake Powell followed immediately by another boat trip on the river below the  dam. Take a boat from Lee's Ferry up the river to within sight of the dam, then shut off the motor and allow yourself the rare delight of a quiet, effortless drifting down the stream. In that twelve-mile stretch of living green, singing birds, flowing water and untarnished canyon walls — sights and sounds a million years older and infinitely lovelier than the roar of motorboats — you will rediscover a small and imperfect sampling of the kind of experience that was taken away from everybody when the oligarch and politicians condemned our river for purposes of their own.

A solution

an exaggeration

a description

a cause and its effect

a description

Explanation:

In this passage from Beyond the Wall: Essays from the Outside, by Edward Abbey (1984), the author describes what the Glen Canyon was like before the dam was built to support the idea that it has been ruined. Abbey makes a detailed description of an area that still resembles what the Glen Canyon used to look like as proof of the way the dam was prejudicial for the Canyon.  

whats the passage

explanation:

you have no answers to choose