题目选项分析

Since 1992, in an attempt to build up the Atlantic salmon population in each of the seven rivers in which salmon still spawn, state officials in Maine have stocked each river with fry raised in hatcheries from eggs produced by wild fish found in that particular river.

Since 1992, in an attempt to build up the Atlantic salmon population in each of the seven rivers in which salmon still spawn, state officials in Maine have stocked the rivers with fry raised in hatcheries from eggs produced by wild fish found in that particular river.