TOEFL Reading: ETS-TOEFL阅读机经 - 5X3Q6E8T75Y6DFGVL$

According to paragraph 4, each of the following is a benefit that Native Americans gained from grassland fires EXCEPT A. increased height of new plants in which to hide B. decrease of insect pest populations C. enhanced productivity of wild food plants D. raised availability of the food their horses preferred