Smart select clean and fill

I have an smart select , the items in the smart select are loaded by sqlite query, so this is my html

  > <a class="item-link smart-select smart-select-init" data-open-in="popover" >
>                                     <select name="" id="mySmartSelect"></select>
>                                     <div class="item-content" >
>                                         <div class="item-inner" >
>                                             <div class="item-title">Smart Select</div>
>                                         </div>
>                                     </div>
>                                 </a>

this is the way I fill the smart select, calling to a local database

db.get.Company(id, function (result) { //call to database to get data
if (result.rows.length > 0 ) {
var element = document.getElementById(mySmartSelect);
for (var i = 0; i < result.rows.length; i++) {
var option = document.createElement(“option”);
option.value = result.rows.item(i).name;
option.text = result.rows.item(i).name;
option.setAttribute(‘data-identificador’, resultado.rows.item(i).name);

So I have two question:
1.- Lets say that the data base just give me one item. How I can push directly that item on the smart select in order to show it . The item does not appear as selected as you can see

2.- I want to clear all the items that the smart select have and load new data. ¿how can i do it?