Birds display a wide variety of courtship behaviors. Which behavior is also a territorial behavior?

Question

flashing feathers to show their health and grooming abilities,

dancing and calling on a lek (communal ground) with other males, competing for female attention,

singing a particular song to help potential mates hear them,

creating a bower (arch) with interesting objects and defending it from rival males

Answer 1

creating a bower (arch) with interesting objects and defending it from rival males