阅读下面的短文，从短文后所给的四个选项中，选出可以填入空白处的最佳选项。
One day, a boy found the cocoon(茧) of a butterfly and brought it home. A few days later, the boy saw a small _____in the cocoon. He sat and watched for several hours as a butterfly struggled to make _____body through that little hole. Suddenly it stopped.
So the boy _____to help the butterfly, thinking the butterfly might be _____. He took a pair of scissors(剪刀) and cut the hole ______. The butterfly came out of the cocoon, but it __     a little different. It had a weak body and small, thin _____. The butterfly didn’t start to fly. In fact, the butterfly spent the rest of its life crawling(爬行) around with a weak body and thin wings. It was never able to fly.
The boy acted with_____but he didn’t understand why it could be like this. When a butterfly crawl out of the cocoon, it must struggle. The hard work of _____out of the cocoon makes the fluid(液体) from the butterfly’s body into its wings. It helps the butterfly be _____to fly. If the butterfly never has to squeeze(挤压) itself out of the cocoon, its wings will never get the fluid and it can never fly.
_____struggles are what we need in our lives. If we lived our lives without any problems, we would never learn or grow. We would not be ____ we could have been and we would never fly.
In our lives, pain and suffering is the key to all windows, and sometimes even _____ growth, without it, there’s no way of life. We can’t avoid _____ or problems. So, next time you are _____ a problem or difficulty, remember the butterfly. Struggle a little–then fly!

A．hole B．worm C．tail D．snake

A．it B．it’s C．itself D．its

A．decided B．asked C．showed D．ordered

A．afraid B．interested C．surprised D．grateful

A．slimmer B．bigger C．shorter D．smaller

A．touched B．sounded C．looked D．smelt

A．wings B．feet C．eyes D．head

A．success B．excitement C．kindness D．humour

A．get B．getting C．to get D．got

A．ready B．quiet C．glad D．used

A．Somewhere B．Something C．Some time D．Sometimes

A．as helpful as B．as weak as C．as strong as D．as creative as

A．repeats B．recommends C．requires D．represents

A．happiness B．difficulties C．pleasure D．hope

A．served with B．growing into C．bringing in D．faced with