来源：https://www.w3schools.com/tags/tag_select.asp
<label for="cars">Choose a car:</label>
<select name="cars" id="cars">
<option value="volvo">Volvo</option>
<option value="saab">Saab</option>
<option value="mercedes">Mercedes</option>
<option value="audi">Audi</option>
</select>