The activity that is part of both private and civic life is 1. learning about politics. This activity involves personal engagement with political knowledge and understanding, which is important both in individual life (private) and in participating in society (civic).
Voting for a candidate (2) is primarily a civic activity, while going to sports games (3) and working at a bookshop (4) are more related to private or personal interests and do not have a direct connection to civic engagement.