某对分查找算法的VB程序段如下:

Dim a(1 To 10) As Integer

Key = Int(Rnd * 32) * 3 + 3

s = 0: i = 1: j = 10

Do While i <= j

    m = (i + j) \ 2

    If Key = a(m) Then Exit Do

    If Key > a(m) Then

        i = m + 1: s = 3 * s + 2

    Else

        j = m - 1: s = 3 * s

    End If

Loop

数组a(1)到a(10)的值依次为“4,7,9,15,24,32,37,54,75,90”，执行该程序段后，s的值不可能为（  ）

A、20

B、80

C、62

D、18