Question

I need to check to see if the user selects a certain value in a drop down menu. If that value is selected I need it to change another drop down menu’s selection.

Here is the html for the first drop down. If Quarterly is selected I need Quarterly to be selected in the 2nd drop down. If anything else is selected there will be no change.

<select id="frequency" name="frequency">
  <option selected="selected" value="">Select One</option>
  <option value="Monthly">Monthly</option>
  <option value="Quarterly">Quarterly (1 Year Minimum, 4 deliveries)</option>
</select>


   <select id="MonthPlan" name="MonthPlan">
      <option selected="selected" value="">Select One</option>
      <option value="3Months">3 Months</option>
      <option value="6Months">6 Months</option>
      <option value="9Months">9 Months</option>
      <option value="12Months">12 Months</option>
      <option value="Quarterly">Quarterly (1 Year Minimum, 4 deliveries)</option>
    </select>

Answer 1

$('#frequency').change(function(){
    if($(this).val() === 'Quarterly'){
        $('#MonthPlan').val('Quarterly');
    }
});

Here a jsFiddle of the code.