Answer: (a)-iii, (b)-iv, (c)- i, (d)-ii
In Latin, the prefix “Olfact-” refers to the sense of smell; thus, the olfactory receptors are present in the nose. The term “gustatory” is connected to the sense of tastes; thus, the gustatory receptors are housed in the tongue. Skin is an integumentary organ that regulates the temperature, and hence the thermoreceptors are found in the skin. Similarly, the photoreceptors allow a person to perceive colorful visuals, and are hence present in the eyes.