An emotional appeal simply refers to when a writer aims to convince people into action through emotion. A writer sometimes also uses emotional appeal for the sake of making his audience relate emotionally to the topic or story.
The correct answer to your question is C.
Option A cannot be correct because it simply states that many organizations have offered recommendations. It does not make the reader feel any sort of emotion. B is also unlikely because it explains that "it" will have an impact, but it does not explain whether the impact will be good or bad. The reader will most likely not feel any emotions towards the meaning of the sentence because it does not give enough information to make the reader understand it through sympathy, sadness, happiness, etc. D is much like option A. D only states a fact but does not lead to any emotional feelings. C is the correct answer because the reader may perhaps feel fear or sadness at the mention of "greatest environmental tragedy."
C) It will be the greatest environmental tragedy. This is emotional appeal because readers don't want a tragedy. It sounds sad. Hope this helps! Please let me know if I'm wrong :)
