有如下VB程序段

Dim c As String, s1 As String

s = Text1.Text

s1 = ""

For i = 1 To Len(s)

    c = Mid(s, i, 1)

    If c >= "A" And c <= "Z" Then c = Chr((Asc(c) - Asc("A")) Mod 10 + Asc("0"))

    If c >= "4" And c <= "9" Then c = Chr(Asc(c) - Asc("4") + Asc("a") + 1)

    s1 = c + s1

Next i

Text2.Text = s1

在文本框Text1中输入“ELQ278yza ”，执行上述程序后，文本框Text2中输出（  ）

A、b1d2efyza

B、4162efyza

C、azyfe2d1b

D、azyfe2614