It is easy to be grateful for the good things, a life of rich fulfillment es to those who are also thankful for the setbacks.
A. that
B. which
C. while
D. when
网友回答
A. that
B. which
(答案→)C. while
D. when
解析：句意：感激美好的事物简单，然而，有成就的人生属于那些感恩挫折的人。此处while是并列连词，前后是对比关系。故选C。