They were all tired, but ____ of them would stop to have a rest.  [ ]

A. any    

B. some    

C. no one    

D. none

阅读下面的程序： Private Sub Command1_Click()For i=1 To 3 For j=1 To i For k=j To 3 x=x+1 Next k Next jNext iPrint x End Sub 程序运行后，单击命令按钮，窗体上输出的结果是

A．3

B．9

C．14

D．21