How can I get user to select only one option?

Have a  question with a "yes" or "no" option. at the moment it allows them to select both. (I was pre-selecting "no" but still allowed them to check both options)

This is not a payment form just registration so has to be done in actual form not at a Paypal level

You can put entry limits in your checkbox field, please see my screenshot below for reference.

Please give it a try and let us know how it goes.

Thanks,
Will see how it goes. I thought that meant I could only get (one) person responding.

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