Which of the following is not present in the fish?

Explanation

Option A: Middle ear and external ear are not found in fishes. All tetrapods i.e. amphibians, reptiles, birds, and mammals have a middle ear with a tympanic membrane. Option B: Fishes do have internal ears that pick up sound through their body. Many fishes rely on their ears to find habitat and mates, swim and avoid predators. Option C: Gills are present in fishes as they have a major role in respiration as well as osmoregulation, excretion of nitrogenous waste, pH regulation, and hormone production. Option D: Fins are also present in fishes and they help in swimming (locomotion), balance, and stability.