Final answer:
The behavior that supports Wrenda's subjective report of acute pain is grimacing and guarding her back.
Step-by-step explanation:
The behavior that supports Wrenda's subjective report of acute pain is c) Grimacing and guarding her back. Grimacing and guarding her back are common behaviors exhibited by individuals experiencing acute pain. These behaviors indicate that Wrenda is experiencing discomfort and trying to protect the affected area. Laughing and chatting with friends (a) and engaging in physical activities (b) are unlikely to support her subjective report of acute pain because they suggest a lack of pain or an ability to carry on with normal activities without discomfort. Ignoring any discomfort (d) also does not support her subjective report of acute pain because it suggests the absence of pain or an unwillingness to acknowledge it.