Hello,
You can try adding a small script like this one in the Form Layout tab of your form:
<script type="text/javascript">
function dropdownValue()
{
document.getElementById("field_name").value=document.getElementById("field_name1").value;
}
</script>
This way when a certain value in selected in the first field it will be set as a default value for the second drop-down field also.
And you will have to add in the Additional Attributes box of the first drop-down field the following code line:
onclick="dropdownValue();"
Let me know if this works for you.
