In fact one cause that leads to the problem. A. cattle isB. cattle areC. cattles areD. t

问题补充：

In fact, one cause that leads to the problem.

A. cattle is

B. cattle are

C. cattles are

D. the cattles are

答案：

A. cattle is

(答案→)B. cattle are

C. cattles are

D. the cattles are

解析：可联系答.案.网客服索取。