题目选项分析

Once numbering in the millions worldwide, the wolf has declined to an estimate of 200,000 in 57 countries, some 11,000 of them to be found in the lower 48 United States and Alaska.

Once numbering in the millions worldwide, wolves have declined to an estimated 200,000 in 57 countries, some 11,000 of them to be found in the lower 48 United States and Alaska.