The correct answer is option A- Social networking 
Google define social capital as a connection between people live and work at a particular place or office that helps them to become a responsible citizen and make society function effectively. 
Social capital is comprised of three factors: 
- Social network 
- Trust reciprocity 
- Shared norms and values 
Moreover, social capital focuses on social relationships that have productive benefits and people interacting share common norms and values.