Пример разметки селекта.

Select

<div class="dropdown bootstrap-select show">
   <select name="sort" id="mse2_sort" data-style="btn-selectpicker border-0" title="" class="selectpicker" tabindex="-98">
      <option class="sort" data-sort="resource|pagetitle" value="asc">А-Я</option>
      <option class="sort" data-sort="resource|pagetitle" value="desc">Я-А</option>
      <option class="sort" data-sort="ms|price" value="asc">Цена ↑</option>
      <option class="sort" data-sort="ms|price" value="desc">Цена ↓</option>
   </select>
   <button type="button" class="btn dropdown-toggle btn-selectpicker border-0" data-toggle="dropdown" role="combobox" aria-owns="bs-select-1" aria-haspopup="listbox" aria-expanded="true" data-id="mse2_sort" title="А-Я">
      <div class="filter-option">
         <div class="filter-option-inner">
            <div class="filter-option-inner-inner">А-Я</div>
         </div>
      </div>
   </button>
   <div class="dropdown-menu show" style="max-height: 338.8px; overflow: hidden; min-height: 126px; position: absolute; will-change: transform; top: 0px; left: 0px; transform: translate3d(0px, 39px, 0px);" x-placement="bottom-start">
      <div class="inner show" role="listbox" id="bs-select-1" tabindex="-1" style="max-height: 322.8px; overflow-y: auto; min-height: 110px;" aria-activedescendant="bs-select-1-0">
         <ul class="dropdown-menu inner show" role="presentation" style="margin-top: 0px; margin-bottom: 0px;">
            <li class="selected active"><a role="option" class="sort dropdown-item active selected" id="bs-select-1-0" tabindex="0" aria-setsize="4" aria-posinset="1" aria-selected="true"><span class="text">А-Я</span></a></li>
            <li><a role="option" class="sort dropdown-item" id="bs-select-1-1" tabindex="0"><span class="text">Я-А</span></a></li>
            <li><a role="option" class="sort dropdown-item" id="bs-select-1-2" tabindex="0"><span class="text">Цена ↑</span></a></li>
            <li><a role="option" class="sort dropdown-item" id="bs-select-1-3" tabindex="0"><span class="text">Цена ↓</span></a></li>
         </ul>
      </div>
   </div>
</div>