为下列句子选择合适的答语。(20分)
( )（1）Is this your sister?
( )（2）What's this?
( )（3）Where are you from?
( )（4）Is that your house?
( )（5）What is it about?
I'm________China.
A．from B．at C．on
London is the________of England.
A．capital B．room C．home
I'm________pupil.
A．a B．an C．/
This is a book________animals.
A．about B．on C．for
the top .