Final answer:
Option B, "I am no one, and everyone is me," indicates that the client is experiencing depersonalization.
Step-by-step explanation:
Depersonalization is a symptom of depersonalization/derealization disorder, which is characterized by a persistent and distressing feeling of being detached from one's own thoughts, feelings, and body. Out of the given statements, the one that indicates depersonalization is option B: "I am no one, and everyone is me." This statement reflects a sense of loss of personal identity and a blurring of boundaries between oneself and others.