<form>

    <select name="cars" id="cars" required>
        <option value="">None</option>
        <option value="volvo">Volvo</option>
        <option value="saab">Saab</option>
        <option value="mercedes">Mercedes</option>
        <option value="audi">Audi</option>
      </select>
<button type="submit">Gönder</button>

</form>