Which of the following is a sign of pain in dogs?

The presence of behaviors such as whining, panting, and restlessness in dogs are strong indicators of pain. Whining can signify distress or discomfort, while panting is often a physiological response to pain or anxiety, especially in situations where a dog is experiencing physical discomfort. Restlessness can suggest that the dog is unable to find a comfortable position due to pain, leading to increased movement and pacing.

Other signs of pain in dogs may include changes in their normal activities, vocalizations indicating discomfort, and altered behaviors related to social interactions. Recognizing these signs is crucial for prompt veterinary assessment and intervention, as they can indicate varying levels of pain, whether acute or chronic.

In contrast, lethargy and lack of appetite can be signs of various health issues, not exclusively pain. Excessive grooming may indicate stress or anxiety rather than pain. Improved social interaction usually suggests a positive emotional state, as dogs in pain typically withdraw from social interactions due to discomfort. Therefore, the behaviors outlined in the correct choice specifically align with recognizing signs of pain in dogs.