The correct answer is option 4: Ear. The smallest bone in the human body is found in the ear. More specifically, it is called the stapes bone or the stirrup bone. It is located in the middle ear, which is responsible for transmitting sound vibrations from the outer ear to the inner ear.

Option 1: The wrist is not the correct answer because the smallest bone is not located in the wrist.

Option 2: The palm is also not the correct answer. The smallest bone is not found in the palm of the hand.

Option 3: The nose is not the correct answer either. Although the nose does contain bones, the smallest bone is not located in the nose.

Therefore, the smallest bone in the human body is indeed found in the ear, specifically the stapes bone or stirrup bone.