It is known that exposure to carbon monoxide is harmful to animals because

Options

A. it reduces `C_(O)` transport
B. it reduces `O_(2)` transport
C. it increases `C_(2)` transport
D. it increases `O_(2)` transport

Answer

b

Explanation

Haemoglobin consist of a protein globin and pigment here. The four portion of iron in name combine with molecule of oxygen. It is an easy reversible reaction to form oxyhaemogiobin . 
`Hb+O_(2)hArrHbO_(2)`
Whereas, the complex formed by the reaction of carbon monooxide and haemoglobin is incredibly strong
`underset"(Haemoglobin)"(Hb+CO)rarrunderset"(Carboxy haemoglobin)"(HbCO)`
As a result of this strong between the haemoglobin and carbon monooxide the haemoglobin looses its affinity to oxygen thus may lead to choking or even death.