Answer: The correct answer is - 3) olfactory receptors neurons that detect smell. 4) photoreceptors neurons that detect light .
1) and 2) statements are correctly matched in the question..
Olfactory receptors are also called odorant receptors. The olfactory receptor neurons detect smell and thus give a sense of smell to the organism. They are present in the nasal cavity.
Photoreceptor neurons are those that detect light and they are present in the retina of eye.
B or d.... hope this helps:)
The answer is “low” pressure areas