The nurse employed in a mental health clinic is greeted by a neighbor in a local grocery store. The neighbor asks the nurse, "How is Mary doing? She is my best friend and is seen at your clinic every week." Which is the most appropriate nursing response?

"Being her friend, you know she is having a difficult time and deserves her privacy."

"Only because you're worried about a friend, I'll tell you that she is improving."

"I cannot discuss any client situation with you."

"If you want to know about Mary, you need to ask her yourself."