My best guess would be A.
Answer:
frightening creatures
heroic characters
supernatural beings
Explanation:
One of the most important elements of ancient Greek mythical literature, as reflected in contemporary literature, is supernatural beings and these show the relationship between mortals and gods which most of the time has to do with the gods transforming to frightening creatures and also, there is always the existence of heroic characters because they are usually a symbol of justice, and fairness.
A
more than one of these could be right but A is the best choice because it is about the PLANNING