What does the phrase "purpled thy nail" refer to in this excerpt from "The Flea" by John Donne?


Cruel and sudden, hast thou since

Purpled thy nail in blood of innocence?

Aan injury the speaker's beloved incurred as he wooed her

Bthe shared blood of the speaker and his beloved in the flea

Cthe loss of the beloved's innocence symbolized by the flea

Dthe beloved's sudden cruel treatment of the speaker