一个的特殊的二级联动问题

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<select id="s1">

    <option value=0>0</option>

    <option value=3>3</option>

    <option value=4>4</option>

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<select id="s2">

    <option value=1>1</option>

    <option value=3>3</option>

    <option value=4>4</option>

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<select id="s3">

    <option value=2>2</option>

    <option value=3>3</option>

    <option value=4>4</option>

</select>