Answer:
A. He was unopposed
Step-by-step explanation:
Stalin was a definition for a dictator. He ruled with fear, and used the police and military to impose his ideas with force if someone was not willing to accept them. He also eliminated everyone that he saw as a political threat, as someone that can oppose him for the office. That pretty much created a situation where there was no one to oppose Stalin, thus he ruled freely without any fear of competition. Even his closest people from the communist party were afraid and would not dare to oppose him for the leading role.