Hide Category fields from a group on Incident form

Reviewing this, I came up with the following onLoad Client script; however, it does not work for me.  Any ideas?

Want to hide or remove from a group when in the Incident form some categories they will not use.

Looking at your example, I switched it to the following on the onLoad Client Script.

Do you know if this is valid?

function onLoad() {
//Type appropriate comment here, and begin script below
g_form.removeOption('category', 'Applications');
g_form.removeOption('category', 'Hardware');
g_form.removeOption('category', 'Inquiry');
g_form.removeOption('category', 'Property');
g_form.removeOption('category', 'Network');
g_form.removeOption('category', 'Security');
}