某VB程序代码如下：
Dim n As Integer
Dim s As String
n = 73
s = ""
Do While n > 0
s = Str(n Mod 8) + s
n = n \ 8
Loop
执行该程序段后，变量s的值是 （ ）

A．"121"

B．121

C．"111"

D．111

某Visual Basic程序如下：
Private Sub Command1_Click()
Dim x As Integer, y As Integer ,a As Integer ,b As Integer
X="0"
y=0
For a="1" To 3
x=x+1
For  b="2" to 4
y=y+1
Next b
Next a
Text1.text=str(a)
Text2.text=str(b)
End Sub
单击Command1按钮后，Text1显示    ①   ，Text2显示    ②   。

某算法流程图如第5题图所示，最后输出s的值是（    ）

A．0.25

B．1

C．2

D．8

阅读下列程序，写出运行结果

Dim a(10) as integer

Dim i as integer

Dim s as integer

For i=1 to 5

  a(i)=i*i

next i

s=a(3)+a(4)

print s

上述程序运行后，变量s的值是________

(加试题) 有程序段
n = 0: i = 1
Do While i <= 4
y = False
For j = 5 To i + 1 Step -1
If a(j) > a(i) Then
y = True
n = n + 1
t = a(j): a(j) = a(i): a(i) = t
End If
Next i
If y = False Then Exit Do
i = i + 1
Loop
数组元素a(1)到a(5)的值依次为“43，18，5，26，51”，经过该程序加工后，变量n的值为( )

A．5

B．4

C．3

D．2