下面可以正确定义2个整型变量和1个字符串变量的语句是【 】

A．Dim n,m As Integer,s As String

B．Dim a％,b$,c As String

C．Dim a As Integer,b,c As String

D．Dim x％,y As Integer,z As Suing

布鲁纳的学习理论。