（23）设有以下函数过程Private Function Fun（a（) As Integer, b As String) As Integer...End Fun

（23）设有以下函数过程

Private Function Fun(a() As Integer, b As String) As Integer

...

End Function

若已有变量声明：

Dim x(5）As Integer, n As Integer, ch As String

则下面正确的过程调用语句是

A）x(o)＝Fun(x, "ch")

B）n＝Fun(n, ch

C）Call Fun x, "ch"

D）n＝Fun(x(5), ch)

请帮忙给出正确答案和分析，谢谢！