阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
In the United States there was an unusual story telling of the daughter of an engineer．One day 36  walking along the bank of a lake, the girl happened to see 20 eggs laid by a wild goose．After some time the girl_37_the mother would not return to the eggs and she  38  to take them home．There she carefully  39  the eggs in the heat of a lamp．Several days  40  , the eggs broke and the baby geese came into the  41 Geese are known to take the first living thing 42  they see as their mother．Thus, to these  43  geese, the girl was their mother．
As they grew, the girl was able to  44  her birds to run across the grass, but she could not teach, them to _45_．The little girl became increasingly worried about this, both when  46  and in her dreams．Suddenly, she thought_47_a clever idea: she would fly a plane to guide them in 48 ．She asked her father for a plane and he made a small one for her．Caring about  49  safety, the father Hew the plane himself．However, the birds didn't  50  him．They all slept in the grass 51 .      
The girl was so worried about it that one day the girl_52_into the plane and started it．Soon the plane left the_53_．Seeing their mother in the air, the birds 54  expanded their wings and   55   She flew the plane freely in the sky, with her young birds following．

A．since B．after C．while D．because

A．realized B．expected C．imagined D．admitted

A．helped B．decided C．afforded D．agreed

A．placed B．protected C．treated D．examined

A．ago B．out C．later D．long

A．family B．house C．home D．world

A．what B．which C．that D．who

A．great B．big C．shy D．young

A．ask B．lead C．want D．allow

A．fly B．race C．swim D．sing

A．asleep B．away C．around D．awake

A．of B．through C．over D．back

A．sky B．heaven C．flight D．plane

A．his B．her C．their D．its

A．respect B．remember C．follow D．receive

A．sadly B．instead C．hardly D．too

A．climbed B．looked C．drove D．fell

A．house B．floor C．water D．ground

A．secretly B．disappointedly C．patiently D．immediately

A．looked away B．set out C．went by D．turned back