A Hispanic Patient Approaches the Asian Nurse And, Standing Very

A Hispanic patient approaches the Asian nurse and, standing very close, touches the nurse's shoulder during their conversation. The nurse begins to step back to 18 to 24 inches, while smiling and nodding to the patient. This situation is most likely an example of:

A) the nurse's need to maintain a professional role rather than a social role.
B) a patient's attempt to keep the nurse's attention.
C) a nurse's need to establish a more appropriate location for conversation.
D) a difference in culturally learned personal space of the nurse and the patient.