题目选项分析

Laos has a land area comparable to that of Great Britain but a population of only four million people, many of whom are members of hill tribes ensconced in the virtually inaccessible mountain valleys of the north.

Laos has a land area that is about the same size as Great Britain's land area, but in Laos with a population of only four million people, many of them are members of hill tribes ensconced in the virtually inaccessible mountain valleys of the north.