Which of the following is a sign that an animal might be in pain?

Vocalization and aggression are significant indicators that an animal may be experiencing pain. When animals are in discomfort, they often express their distress through vocalizations such as whining, growling, or yelping. Additionally, aggression can be a defensive response to pain; animals that are hurting may lash out because they feel threatened or vulnerable. This behavior can serve as a communication tool, signaling to others that they are in a state of distress. In contrast, increased appetite and energy, calm behavior, trust, playfulness, and excitement are generally associated with comfort and well-being, rather than pain. Recognizing vocalization and aggression as signs of pain is crucial for timely assessment and intervention in veterinary care.