59（）

A．Separating usable products from trash.
B．Processing them so that they can be used to replace more expensive materials.
C．Returning them to markets as new products.
D．Splitting them into three categories: hazardous items, combustible waste and non-combustible wast

A．The author has worked in China for 37 years.
B．Cycling is not as safe as it was in the 1960s.
C．The unique character of the old Beijing is disappearing.
D．You cannot buy anything you like though you have money.