Answer:
Correct answer is unlimited, because Czars had full authority in the country who was able to bring all the decisions in the country. He could start wars or change laws for example.
Step-by-step explanation:
Authority of Czar was unlimited until the beginning of 20th Century. There were no one institutions that could restrict his authority.
Even when Duma was introduced as a political body it hasn't change much, as it didn't restrict him. Finally, during the war people decided to overthrew this regime.