Radio Buttons - None Selected

I have two radio buttons. I need the user to select one, but the first one is selected by default. How can I remove that and NOT have one selected.

I'm using the wizard to create my form.

ChronoForms: 4.0 RC1.9

Thank you!!

Hi LikeStuff,

Remove the entry from the 'Field Default Value' box in the element configuration.

Bob