Again, differences between people and the opportunity for natural selection to take ad

参考答案:

68. 【译文】人与人之间的差异以及自然选择利用该差异的机会减少了。 【解析】注意 differences between people和 the opportunity for natural selection to take advantage of it是两个并列的主语，千万不要理解成 people与the opportunity 是between 的并列宾语。另外注意句中的 it 指代的是 differences between people。 重点词组：natural selection 自然