For your answer to this question, which is a more specific version of question 21, you can just concentrate on what you like doing best. What really fires up your enthusiasm? How do you like to spend your time after work? The activity you pick has to be something other than watching TV unless you watch a specific type of programme on TV such as history programmes or wildlife documentaries that you can talk about in some detail. Seeing friends is something that we all do, unless you go hill walking with yours or plan regular holidays together, in which case it will do fine. The stress should be on the activity, ie something in which you are actively involved.
Please don’t be tempted to make up an exotic hobby for this question or you may find that the interviewer, to whom you have just bluffed about being a karate expert, has a black belt in that sport herself. You would find it impossible to continue making things up if you were sitting across from an expert in that subject and it could lose you your chance of the job. It is better to talk about something real that you enjoy a lot, even if it is not very exciting. Let your enthusiasm for the activity do the talking.