下述骨折中，哪种易出现骨折不愈合、骨坏死（）

A.椎体压缩骨折

B.跟骨骨折

C.干骺端嵌插骨折

D.股骨颈头下型骨折

E.Colles骨折

After graduating from college, I took some time off to go traveling,       turned out to be a wise decision.

A．that

B．which

C．when

D．where