TOEFL Listening: ETS-TOEFL听力机经 - 5R51EA9UW69Y_B51P$

What does the professor imply when he mentions that Bryce Canyon's hoodoos are shrinking? A. There are many ways to stop the destruction of the hoodoos. B. Tourists at Bryce Canyon are damaging the hoodoos. C. The hoodoos are shrinking at a much slower rate than they were before. D. The same processes that created the hoodoos are also destroying them.