________ parents may have a stronger desire to see their children step into the world of ________.[ ]

A. Poor; rich  

B. The poor; rich

C. Poor; the rich  

D. The poor; the rich

对外贸易（foreign trade）是指一个国家（地区）同别的国家（地区）所进行的商品和劳务交换活动的总称。