流通过程的商业交易与物流的分离是由于( )造成的。

A．经济复杂

B．商品买卖

C．成本推动

D．效率经济

—What can you see in the picture?

—I can see a farm. And there ______ a lot of animals on it. [ ]

A. is

B. are

C. will be

D. be