Answer:
Option C
Step-by-step explanation:
When Delta Advertises, United best strategy is to Advertise since payoff is higher ($9,000 > $1,000).
When Delta Does not advertise, United best strategy is to Advertise since payoff is higher ($16,000 > $11,000).
When United Advertises, Delta's best strategy is to Advertise since payoff is higher ($9,000 > $1,000).
When United Does not advertise, Delta's best strategy is to Advertise since payoff is higher ($16,000 > $11,000).
Thus, from the above we can conclude that the correct option is C.