Answer:
D. Emotions
Step-by-step explanation:
In the given passage, the figurative meaning of the phrase "the waves" is:
D. Emotions
The waves in this context symbolize emotions. The description of the waves drawing back, flinging, beginning, ceasing, and starting again with a slow and tremulous cadence suggests the fluctuation and intensity of human emotions. The mention of the waves bringing "the eternal note of sadness in" further emphasizes the emotional depth and melancholic tone of the scene.