They lost their way in the forest, and ___ made matters worse was that night began to fall.
A:it
B:which
C:that
D:what
人体健康离不开化学,下列有关叙述正确的是 ( )
《论语》中有一句话“己欲立而立人,己欲达而达人”,说明人与人之间要理解。理解他人的关键是( )