Multiple Dynamic Javascript Dropdowns?

Multiple Dynamic Javascript Dropdowns?

I have currently got a 2-tier javascript drop down box attached to my
form, and i am looking to add another 3-tiers, but completely seperate to
my current javascript and can't unfortunately figure it out (quite new to
javascript :( )
Here what I have so far, it all works ( not even sure what framework to
select on fiddle for it to display properly lol :( the embarassment haha
http://jsfiddle.net/CEuZY/
function setOptions(chosen) {
var selbox = document.myform.opttwo;
selbox.options.length = 0;
if (chosen == " ") {
selbox.options[selbox.options.length] = new Option('Please Select
Prompty Category', ' ');
}
if (chosen == "1") {
selbox.options[selbox.options.length] = new Option('123213123123',
'oneone');
selbox.options[selbox.options.length] = new Option('23123123123',
'onetwo');
}
if (chosen == "2") {
selbox.options[selbox.options.length] = new Option('23121312312',
'twoone');
selbox.options[selbox.options.length] = new Option('3211231232',
'twotwo');
selbox.options[selbox.options.length] = new Option('2131223213',
'twothree');
selbox.options[selbox.options.length] = new Option('32123213213',
'twofour');
}
if (chosen == "3") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'threeone');
}
if (chosen == "4") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'fourone');
}
if (chosen == "5") {
selbox.options[selbox.options.length] = new Option('23213123123',
'fiveone');
selbox.options[selbox.options.length] = new Option('2312132312',
'fivetwo');
selbox.options[selbox.options.length] = new Option('12312123213',
'fivethree');
selbox.options[selbox.options.length] = new Option('21213231321',
'fivefour');
selbox.options[selbox.options.length] = new Option('213213213',
'fivefive');
selbox.options[selbox.options.length] = new Option('23213132123',
'fivesix');
}
if (chosen == "6") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'sixone');
}
if (chosen == "7") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'sevenone');
}
if (chosen == "8") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'eighone');
}
if (chosen == "9") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'nineone');
}
if (chosen == "10") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'tenone');
}
if (chosen == "11") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'elevenone');
}
if (chosen == "12") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'twelveone');
}
if (chosen == "13") {
selbox.options[selbox.options.length] = new Option('Email',
'thirteenone');
selbox.options[selbox.options.length] = new Option('Letter',
'thirteentwo');
selbox.options[selbox.options.length] = new Option('Phone Call',
'thirteenthree');
selbox.options[selbox.options.length] = new Option('Text',
'thirteenfour');
}
if (chosen == "14") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'fourteenone');
}
if (chosen == "15") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'fifteenone');
}
if (chosen == "16") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'sixteenone');
}
if (chosen == "17") {
selbox.options[selbox.options.length] = new Option('Camera',
'seventeenone');
selbox.options[selbox.options.length] = new Option('Power',
'seventeentwo');
selbox.options[selbox.options.length] = new
Option('Keypad/Buttons', 'seventeenthree');
selbox.options[selbox.options.length] = new Option('Screen',
'seventeenfour');
selbox.options[selbox.options.length] = new Option('Microphone',
'seventeenfive');
selbox.options[selbox.options.length] = new Option('Speaker',
'seventeensix');
selbox.options[selbox.options.length] = new Option('Software',
'seventeenseven');
selbox.options[selbox.options.length] = new Option('Other',
'seventeeneight');
}
if (chosen == "18") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'eighteenone');
}
if (chosen == "19") {
selbox.options[selbox.options.length] = new Option('Not
Applicable', 'nineteenone');
}
}
Any help is appreciated <3