单项选择题

窗体上命令按钮Command1的事件过程如下:
Option Base 1
Private Sub Command1_Click()
Dim a(4,4)As Variant
For i=1 To 4
For j=1 To 4
a(i,j)=(i-1)*3+j
Next j
Next i
For i=3 To 4
For j=3 To 4
Print a(i,j)
Next j
Next i
End Sub
该程序执行后,输出结果是( )。

A.9
10
12
13
B.7
10
12
13
C.9
12
10
13
D.8
11
9
12