Answer:
C. A single individual would have to gain control from an elite few.
Explanation:
In order to change an oligarchy into an autocracy, a single individual would have to gain control from an elite few. Autocracy refers to a system of government in which one person with absolute power rule over the whole country. In autocracy, a high rank military general have absolute power because the whole military is present under it and he can maintain its control over th country with the use of military forces.