I have up to 3 dropdown lists that I can select using javascript functions. Depending on what I select in the first dropdown loads what is in the 2nd drop down and so on. i want to be able to select the first drop down and it skips the 2nd one and displays the 3rd one. How do I do that with the current functions I am using.

Code:
function cboSourceChange(){
		var iSource = document.frmHarvestForm.cboSource.options[document.frmHarvestForm.cboSource.selectedIndex].value;
		var iSub1 = document.frmHarvestForm.cboSub1.options[document.frmHarvestForm.cboSub1.selectedIndex].value;
		var iSub2 = document.frmHarvestForm.cboSub2.options[document.frmHarvestForm.cboSub2.selectedIndex].value;
		var dtBeginDate = document.frmHarvestForm.txtBeginDate.value;
		var dtEndDate = document.frmHarvestForm.txtEndDate.value;
		var iIndCert = document.frmHarvestForm.cboIndCert.value;
		location.replace("HarvestBoard.asp?cboSource="+iSource+"&cboSub1=0&cboSub2=0&cboSub3=0&txtBeginDate="+dtBeginDate+"&txtEndDate="+dtEndDate+"&cboIndCert="+iIndCert);
	}
	function cboSub1Change(){
		var iSource = document.frmHarvestForm.cboSource.options[document.frmHarvestForm.cboSource.selectedIndex].value;
		var iSub1 = document.frmHarvestForm.cboSub1.options[document.frmHarvestForm.cboSub1.selectedIndex].value;
		var dtBeginDate = document.frmHarvestForm.txtBeginDate.value;
		var dtEndDate = document.frmHarvestForm.txtEndDate.value;
		var iIndCert = document.frmHarvestForm.cboIndCert.value;
		location.replace("HarvestBoard.asp?cboSource="+iSource+"&cboSub1="+iSub1+"&cboSub2=0&cboSub3=0&txtBeginDate="+dtBeginDate+"&txtEndDate="+dtEndDate+"&cboIndCert="+iIndCert);
	}
	function cboSub2Change(){
		var iSource = document.frmHarvestForm.cboSource.options[document.frmHarvestForm.cboSource.selectedIndex].value;
		var iSub1 = document.frmHarvestForm.cboSub1.options[document.frmHarvestForm.cboSub1.selectedIndex].value;
		var iSub2 = document.frmHarvestForm.cboSub2.options[document.frmHarvestForm.cboSub2.selectedIndex].value;
		var dtBeginDate = document.frmHarvestForm.txtBeginDate.value;
		var dtEndDate = document.frmHarvestForm.txtEndDate.value;
		var iIndCert = document.frmHarvestForm.cboIndCert.value;
		location.replace("HarvestBoard.asp?cboSource="+iSource+"&cboSub1="+iSub1+"&cboSub2="+iSub2+"&cboSub3=0&txtBeginDate="+dtBeginDate+"&txtEndDate="+dtEndDate+"&cboIndCert="+iIndCert);
	}
	function cboSub3Change(){
		var iSource = document.frmHarvestForm.cboSource.options[document.frmHarvestForm.cboSource.selectedIndex].value;
		var iSub1 = document.frmHarvestForm.cboSub1.options[document.frmHarvestForm.cboSub1.selectedIndex].value;
		var iSub2 = document.frmHarvestForm.cboSub2.options[document.frmHarvestForm.cboSub2.selectedIndex].value;
		var iSub3 = document.frmHarvestForm.cboSub3.options[document.frmHarvestForm.cboSub3.selectedIndex].value;
		var dtBeginDate = document.frmHarvestForm.txtBeginDate.value;
		var dtEndDate = document.frmHarvestForm.txtEndDate.value;
		var iIndCert = document.frmHarvestForm.cboIndCert.value;
		location.replace("HarvestBoard.asp?cboSource="+iSource+"&cboSub1="+iSub1+"&cboSub2="+iSub2+"&cboSub3="+iSub3+"&txtBeginDate="+dtBeginDate+"&txtEndDate="+dtEndDate+"&cboIndCert="+iIndCert);
	}