Sonar system is found in A) Otter B) Bat C) Whale D) Both B and C

The sonar system, or echolocation, is found in animals like bats and whales. Bats use echolocation to navigate and hunt in the dark by emitting high-frequency sound waves that bounce back from objects. Whales also use a form of echolocation to communicate and detect prey or obstacles in the ocean. While otters have sophisticated sensory systems, they do not rely on echolocation. Therefore, the correct answer is D) Both B and C.