How do I create a script to show a particular field based on selection of a 1 choice radio button

How do I create a script to show a particular field based on selection of a 1 choice radio button

In other words I may want the field 'Docket Number' to show (hidden on form load) when  radio button with one choice is shown (let's say button says 'In Foreclosure'). Please advise. Thanks in advance!