给加粗的字选择合适的解释。

1．—件件古代发明，是我们祖先智慧的结晶。[ ]

A．物质变成的晶体。  

B．比喻珍贵的成果。 

2．集邮者得到的益处是非常多的。[ ]

A．增加。    

B．利，有好处的。    

C．更。

—Peter, is there anything else you want to know about China?

—Yes, I am stll wondering __________ .[ ]

A. how is Chinese paper cut made

B. how was the Great Wall built in ancient times

C. why the Chinese people like to play the dragon dance

D. why do the Chinese people eat rice dumplings at Dragon Boat Festival