Which of the following is NOT a work by Ovid?

The correct answer is C, "De Rerum Natura," as it is not a work by Ovid. Instead, it is an epic philosophical poem written by Lucretius, a Roman poet and philosopher. This poem explores Epicurean philosophy and the nature of the universe, delving into atomism and the nature of the soul.

In contrast, the other titles are indeed works attributed to Ovid. "Metamorphoses" is one of Ovid's most famous works, composed of mythological stories that revolve around transformation, showcasing his skill in narrative poetry. "Heroides," also by Ovid, consists of a series of letters written in the voices of mythological heroines, reflecting Ovid's exploration of love and longing. "Medea" is a lesser-known work associated with Ovid, which retells the myth of Medea, focusing on themes of betrayal and vengeance. Thus, recognizing the authorship of these classic texts is crucial for understanding their thematic connections and historical context in Roman literature.