Creating world peace is a rather difficult goal, calls for efforts of many generations.
A. one that
B. one
C. that
D. it
网友回答
(答案→)A. one that
B. one
C. that
D. it
解析： 考查：one作a rather difficult goal的同位语，后一个分句是定语从句，one做先行词，从句中缺少主语，故用that,句意；创造世界和平是一个非常困难的目标，一个需要许多代人努力奋斗的目标。故选A。