Nico is a passenger in a car driven by Owen, whose reckless driving causes an accident, injuring himself. Nico, uninjured, accompanies Owen to Parkside Hospital in an ambulance. The ambulance is hit by a car driven by Quin, and Nico is injured. Nico files a suit against Owen, alleging negligence. The element most likely to be a question for the court to decide is

causation in fact.

proximate cause.

the duty of care.

the injury requirement.