两道英语语法 急
The promising young man specializing______biotech is______his way to success.
A.at on
B.in on
C.at in
D.on in
请问这两个空分别是什么用法
There is a real possibility that these animals could be frightened,_______a sudden loud noise.
A.being there
B.there was
C.should there be
D.there having been
请问这到题为什么选C不选D