Dim a(1 to 20) As Integer

For i=2 to 10

For j=2 to 20\i

a(i*j)=a(i*j) +1

Next j

Next i

该程序段运行后，数组a中元素值为0的个数是（  ）

c = 1: s = 10

Do While c <= s

    For i = s To c + 1 Step -1
        If      Then

            t = a(i - 1): a(i - 1) = a(i): a(i) = t
        End If

    Next i
    For i=

        If     Then

            t = a(i + 1): a(i + 1) = a(i): a(i) = t
        End If

    Next i

    c = c + 1
    s = s - 1

Loop

上述程序段三个方框处的语句分别为（  ）

item={"竞技类":["铁人三项","电子竞技","霹雳舞"],"球类":["足球","篮球","乒乓球"],

"对抗性":["拳击","跆拳道","卡巴迪","击剑"],"水上":["跳水","龙舟","帆船"]}

print(item["对抗性"][2][::-1])

执行该程序段后，输出的结果是（     ）