Dropdowns are wrapped with an input field - the same pattern for hint, help and error texts apply.
<div class="input-field"> <label for="input">label</label> <select class="dropdown-input" id="input" name="input" aria-invalid="false" aria-errormessage="input-validation" required> <option value="">placeholder</option> <option value="option-1">option</option> <option value="option-2">option</option> <option value="option-3">option</option> </select> <div id="input-validation" class="input-field__validation">validation message</div> </div>
When rendering a component that has a preselected option, you can set it with the selected attribute.
<div class="input-field"> <label for="input-selected">label</label> <select class="dropdown-input" id="input-selected" name="input-selected" aria-invalid="false" aria-errormessage="input-selected-validation" required> <option value="">placeholder</option> <option value="option-1" selected>option</option> <option value="option-2">option</option> <option value="option-3">option</option> </select> <div id="input-selected-validation" class="input-field__validation">validation message</div> </div>
<div id="date-selector-month-year" class="flex gap-m"> <select class="dropdown-input"> <option value="">MM</option> <option value="January">January</option> <option value="February">February</option> <option value="March">March</option> <option value="April">April</option> <option value="May">May</option> <option value="June">June</option> <option value="July">July</option> <option value="August">August</option> <option value="September">September</option> <option value="October">October</option> <option value="November">November</option> <option value="December">December</option> </select> <select class="dropdown-input"> <option value="">YYYY</option> <option value="2025">2025</option> <option value="2024">2024</option> <option value="2023">2023</option> <option value="2022">2022</option> <option value="2021">2021</option> <option value="2020">2020</option> <option value="2019">2019</option> <option value="2018">2018</option> <option value="2017">2017</option> <option value="2016">2016</option> <option value="2015">2015</option> </select> </div>
<div id="date-selector-year"> <select class="dropdown-input"> <option value="">YYYY</option> <option value="2025">2025</option> <option value="2024">2024</option> <option value="2023">2023</option> <option value="2022">2022</option> <option value="2021">2021</option> <option value="2020">2020</option> <option value="2019">2019</option> <option value="2018">2018</option> <option value="2017">2017</option> <option value="2016">2016</option> <option value="2015">2015</option> </select> </div>