Answer :
There are several types of conflicts in literature:
You have:
1. Man versus Self
2. Man versus another character
3. Man versus nature (ex. To build a Fire by Jack London)
4. Man versus Society (ex: Atlas Shrugged)
In this case I would think that the conflict is found in D: Perseus's effort to escape from the Gorgons after he kills Medusa.
The reason why I feel that D is the best option is because There is a cause and effect of the conflict. Pereus caused a death and now that brings conflict into the picture especially since it says he has to put effort into escaping the other characters (Gorgons).
Good luck and I hope this helped.