What is a sign of a relaxed state in both cats and dogs?

Normal pupil size is indicative of a relaxed state in both cats and dogs. When animals are calm, their pupils typically appear neither dilated nor constricted, reflecting a state of comfort and security. This physiological response is part of their body's way of communicating that they are not in a stressful or threatening situation.

In contrast, a high tail position more commonly signifies excitement or alertness rather than relaxation. A fixed gaze might indicate intense focus or stress, as the animal may be concentrating on a perceived threat or stimulus. Active vocalization often suggests that a pet is engaged, anxious, or seeking attention, which does not correlate with a relaxed demeanor. Therefore, normal pupil size is the most reliable sign of a relaxed state among the options provided.