The third alternative is correct (C).
A Government that operates based on fear and ideologies can happen in an Oligarchy, but it can also happen in dictatorships, republics and even in democracy, when populist and extreme governments are in power. For example the left in Venezuela and the most recent case, the extreme right in Brazil.
What characterizes an oligarchic government is that power is concentrated in the hands of the few, usually in the hands of a powerful family.