A decent answer would be: "I do have a driving license. I don't have any need for a car right now, so I'd like to know why the job would require a car".
For example, if you were to work from home generally, but once a month you need to go to a place that cannot be reached by public transport, then renting a car would be much cheaper for me than buying a car just for that. Or public transport plus 20 miles in an Uber.
Many jobs don't require driving a car at all, so you'd definitely want to know why they think it is required.