Carbon monoxide impairs hemoglobin's oxygen-binding capacity

Steps:

• Hemoglobin in red blood cells binds oxygen for transport to organs.
• Carbon monoxide binds to hemoglobin more tightly than oxygen, forming carboxyhemoglobin.
• This blocks oxygen attachment sites on hemoglobin.
• Reduced oxygen delivery starves body's organs of oxygen.

Why B is correct:

• Hemoglobin's primary function is reversible oxygen binding and transport; CO's higher affinity (200–250 times stronger) prevents this per gas physiology laws.

Why the others are wrong:

• A: Clotting involves platelets and fibrinogen, unaffected by CO binding to hemoglobin.
• C: Antibody production by lymphocytes is an immune process, not linked to gas transport.
• D: Adrenaline dissolves in plasma for transport, independent of hemoglobin.

Final answer: B