Q.

When a person is suffering from severe cold, he or she can not:

1 differentiate the taste of an apple from that of an ice-cream  
2 differentiate the smell of a perfume from that of an agarbatti.  
3 differentiate red light from green light.  
4 differentiate a hot object from a cold object.  

Ans.

(2)

Mucus in the nasal passages thickens during a cold, preventing scent molecules from reaching the olfactory receptor cells. As a result, the brain receives no information identifying the odour, making it impossible to distinguish the smell of a perfume from that of an agarbatti.