Content Type vs. Taxonomy | Example TV Series
I would do it the A) way and use Entity reference module to "link" episodes to series. That way you can use watever fields you want in your content types (including taxonomy for genre for example). 


  The Entity Reference Module is used to relate entities (nodes, terms,
  users, etc...) to one another.


After that, you can display content types with Views showing Series with list of episodes.