题目选项分析

To help counteract the adverse effects of trout stocking on the amphibian populations in certain mountain lakes, biologists are recommending that some states cut back on trout stocking and even remove the trout from some popular fishing lakes.

To help counteract the adverse effects of trout stocking on the amphibian populations in certain mountain lakes, biologists are recommending cutting back on trout stocking on the part of some states and even that they remove them from some popular fishing lakes.