TOEFL Reading: ETS-TOEFL阅读机经 - 3841555JMOL6V5BOL$

According to paragraph 5, why do environmental groups want the Hetch Hetchy Dam removed? A. To restore salmon and steelhead runs to the Snake River B. To allow access to the headwaters of the Columbia River C. To increase the size of Yosemite National Park D. To restore a valley to its original beauty