Final answer:
The nurse should ask the man and woman to step out, creating a safe environment for the child to disclose information about their injuries without fear of retribution.
Step-by-step explanation:
In this clinical scenario, the nurse is presented with potential signs of child abuse, including multiple bruises at varying stages of healing and avoidant behavior by the boy towards the man. The professional and appropriate course of action would be to discreetly separate the child from the adults in order to conduct a private assessment. Therefore, the nurse should ask the man and woman to step out to ensure the boy's safety while further evaluating the situation.
Confronting the suspected abuser or conducting questioning in front of them may escalate the risk to the child. It's essential for medical professionals to create a safe environment where a potentially abused child feels secure enough to disclose any information about their injuries without fear of retribution. Once the child is alone, the nurse can then gently ask open-ended questions to determine the cause of the injuries and ensure the child receives the appropriate care and protection.