—The actor donated a lot of money. 　　　　 a generous man he is!

—　　　　.

A．What; So is he

B．What; So he is

C．How; So is he

D．How; So he is

程序的流程图如下图所示，采用路径覆盖法进行测试，则至少需要几个测试用例可以覆盖所有可能的路径______。