$(document).ready(function() {
    $("#price1").click(function() {
      $("#select2").removeClass("active");
      $("#select1").toggleClass("active");
    });
    
    $("#price2").click(function() {
      $("#select1").removeClass("active");
      $("#select2").toggleClass("active");
    });
});

select {
  display: none;
}

.active {
  display: block;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

<button id="price1">Price 1</button>
<button id="price2">Price 2</button>

<select id="select1" class="active">
  <option selected>Max </option>
  <option>1</option>
  <option>2</option>
  <option>5</option>
  <option>6</option>
  <option>7</option>
  <option>8</option>
</select>

<select id="select2">
  <option selected>Max </option>
  <option>9</option>
  <option>10</option>
  <option>11</option>
  <option>12</option>
  <option>13</option>
  <option>14</option>
</select>