The issue with (C) is that even if you assume that New Planet is Discovered parallels New Currency in Passage A, Passage B is a poor parallel to Planet or Asteroid Scientists Debate because it discusses the proper application of tax law to the virtual wealth/ currency rather than debating if it is Currency (Planet) or another concept (Asteroid). (D) on the other hand parallels both passages nicely - Biologists Created New Species in Lab - Players Created New Currency in Online Games and Artificially Created Life: How Patent Law Applies - Virtual Assets: How Tax Law Applies.
Let me know if this makes sense and if you have any further questions.