有如下程序: Option base 1 Private Sub Command1_Click Dim arr(10) Arr=Array(10,35,28,90,54,68,72,90) For Each a In arr If a>50 then Sum=sum+a End If Next a End Sub 运行上述程序时出现错误,错误之处是
A. 数组定义语句不对,应改为Dim arr B. 没有指明For 循环的终值 C. 应在For语句之前增加sum=0 D. Next a 应改为next