The answer is D) “Philomel becometh dumb".
Two key pieces of information are needed to correctly answer the question:
1) Remember that "dumb" also means, and long ago more commonly meant, unable to speak, or mute.
2) Philomel is a princess in Greek Mythology who is raped by her sister's husband and is transformed to a nightingale, a songbird whose song is generally seen as sorrowful.
Philomel becoming dumb means the princess, transformed into a nightingale, has lost her ability to fill the air with her sorrowful song, her one expression of sadness that she has. This is what makes it an auditory appeal.