The correct option is B Frog
In a frog, the exchange of gases with the surrounding atmosphere for respiration, takes place through the skin, in the lungs and on the lining of the mouth. The skin is composed of thin membranous tissue that is quite permeable to water and contains a large network of blood vessels. The thin membranous skin allows the respiratory gases to readily diffuse directly down their gradients between the blood vessels and the surroundings. When the frog is out of the water, mucus glands in the skin keep the frog moist, which helps absorb dissolved oxygen from the air.
So, the correct answer is option B.