Question

The first decade in the 21st century is the one ______ many significant advances are made in China.

A．that

B．in which

C．which

D．where

Answer 1

B

考查定语从句，先行词是The first decade in the 21st century表示时间，定语从句中缺少的是时间状语，用when或in which引导定语从句，句意是：21世纪的第一个十年是中国取得很多重大进步的时间。选B。