(a) Olfactory receptors--- (iii) Nose

(b) Thermo receptors (temperature receptors) --- (iv) Skin

(c) Gustatoreceptors--- (i) Tongue

(d) Photoreceptors--- (ii) Eye

Explanation: Receptors are molecules that receive signals from outside of a cell.

Olfactory receptors are expressed in the cell membranes of olfactory receptor neurons and are responsible for the detection of odorants (i.e., compounds that have an odour) which give rise to the sense of smell.

Thermo receptors are specialized nerve cells that are able to detect differences in temperature.

Gustato receptors are taste buds. They facilitate the sensation of taste.

A photoreceptor cell is a specialized type of neuron found in the retina. Photoreceptors convert light into signals that can stimulate biological processes.