Answer:
B.Assumption of the risk doctrine.
Step-by-step explanation:
B is the correct answer because according to that doctrine someone is voluntarily encountering the risk therefore cannot sue the defendant. For eg alot of places do this where injury can occur like scuba diving, skating complexes, bungee jumping, and other sports. Because as a participant you know that you might encounter a risk but you are doing it voluntarily hence you cannot sue for any liabilities.