Answer: The lines of A Midsummer Night's Dream that explain why Demetrius may not be as good a suitor for Hermia as Lysander are C) "Demetrius, I'll avouch it to his head, Made love to Nedar's daughter, Helena".
Step-by-step explanation: A Midsummer Night's Dream is a play written by William Shakespeare. It focuses on the love story of Hermia and Lysander and the obstacles they face to be together. One of these obstacles is Demetrius, the man that Hermia's father wants her to marry with. However, in the play, Demetrius is a former lover of Helena, Hermia's friend. In order to indicate that Demetrius may not be as good a suitor for Hermia as Lysander, Lysander refers to the fact that Demetrius "made love to Nedar's daughter, Helena". Therefore, option C. is the correct one.