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<option value="" selected>请选择 </option>
<option value="服装">服装 </option>
<option value="表演">表演 </option>
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<option value="计算机">计算机 </option>
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<html><head>
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<title>新建网页 1</title>
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<form name=form2 action="">
<select name="a" id="a">
<option value="" selected>请选择 </option>
<option value="服装">服装 </option>
<option value="表演">表演 </option>
</select>
<select name="b" id="b">
<option value="" selected>请选择 </option>
<option value="计算机">计算机 </option>
<option value="机械">机械 </option>
</select>
<select name="c" id="c">
<option value="" selected>请选择 </option>
<option value="图书">图书 </option>
<option value="杂志">杂志 </option>
</select>
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