Once you decide to do the things you fing___,make every effort!A worth being done B.worth doing.为什么不是A?

Once you decide to do the things you fing___,make every effort!A worth being done B.worth doing
.为什么不是A?

fing?是find吧
这是考察了定语从句的用法
do the things （which/that）you find worth doing
应该是用主动表被动,要不然就是搭配问题
be worth doing
be worthy of being done