Final answer:
The sentence uses a metaphor to describe the woman as being overwhelmed by her memories, similar to being submerged by the depths of the sea.
Step-by-step explanation:
The sentence "As in the depths of many seas, her heart was drowned in memories" suggests that the woman felt overwhelmed by her memories, meaning that the correct answer is A: She felt overwhelmed by her memories. The phrase uses a metaphor comparing the depths of the sea to the depth and intensity of her memories that engulf her much like the sea would. This metaphor indicates a sense of being submerged or enveloped wholly by these past experiences or emotions.