After a Hurricane Hit Halifax a Few Years Ago, Local

Short Answer

After a hurricane hit Halifax a few years ago, local retailers increased the price of milk and gas by 50% in one day, even though all other stores in the province did not increase prices. These retailers were engaging in
conflict-of-interest pricing.
sharp business practices.
crisis-based pricing.
price gouging.
It is not possible to tell from the information that is given.