I’m building a car insurance calculator which gives users to ability to select a car model and their age range, and upon clicking a button, a figure should pop up that gives the user the price of insurance according to this.

The if statement I’ve made, which uses the .checked and .selected methods aren’t functioning and I can’t work out why.

When i remove the second half of the if statement (&& document.getElementByID(“band1”).selected == true), it works fine.

What could be the problem? See full block of relevant code below

     Function: 



        function calculateInsurance(){   
        var msg = document.getElementById('insurance');
        var poloinsurance1 = poloPrice * bandone;
        var poloinsurance2 = poloPrice * bandtwo;
        var poloinsurance3 = poloPrice * bandthree;
        var poloinsurance4 = poloPrice * bandfour;


         if (document.getElementById("VWPoloCheck").checked == true &&       document.getElementByID("band1").selected == true) {
         
         document.getElementById('insurance').innerHTML =  "£" + poloinsurance1;

       }
     
     }

         HTML:

      <table> 
      <tr>
      <th> </th></th> 
      <td><input type="checkbox" id="VWPoloCheck" value="3500" onclick="poloCheck();"></input></td>
      <tr>
      </table>

      <div>

      <select>
      <option id="band1">16-24</option>
      <option id="band2">25-32</option>
      <option id="band3">33-50</option>
      <option id="band4">51-75</option>
      </select>
      </br>

      <button id="insurancecost" style="margin-top: 2.5%;" onclick="calculateInsurance();">  Calculate </button>

     <p id="insurance"></p>
     </div>