The answer is D.
Exploration:
She usually has to ask people to repeat their comments in a simpler way so she can follow along. In paragraph 21, Rachel Kolb writes, "I don't like superficial remarks and predictable rejoinders, but staying in shallow waters is better than sinking." Here, "staying in shallow waters" means that she has to keep conversations safe and simple by asking people to repeat or rephrase their comments so she can understand them, rather than engaging in complex or spontaneous discussions that she might not follow.