Posttraumatic stress disorder (PTSD) is a stress-related psychiatric condition that may develop after exposure to a traumatic event. NREMT education addresses PTSD particularly in the context of crisis intervention, behavioral emergencies, and responder mental health awareness.

Option C (Flashback phenomena) is correct. Flashbacks are a hallmark feature of PTSD and involve intrusive, vivid recollections of the traumatic event that may feel as though it is happening again. These episodes can be triggered by sights, sounds, or smells associated with the trauma.

Option E (Difficulty concentrating) is also correct. Patients with PTSD frequently experience cognitive symptoms such as impaired concentration, memory problems, and difficulty completing tasks. These symptoms result from persistent hyperarousal and stress responses.

Option A is incorrect because PTSD is associated with nightmares, not an inability to dream.

Option B is incorrect because violent behavior is not a defining or consistent feature of PTSD, although irritability may be present.

Option D is incorrect because increased compassion is not a recognized symptom.

NREMT emphasizes recognizing PTSD symptoms to ensure appropriate patient interaction, safety, and referral for further care.