【单选题】Despite improvements in treatment for asthma, the death rate from this disease has doubled during the past decade from its previous rate. Two possible explanations for this increase have been offered....
A.
populations have doubled in the past decade.
B.
Records of asthma deaths are as accurate for the past twenty years as for the past ten years.
C.
Evidence suggests that bronchial inhalers make the lungs more sensitive to irritation by airborne pollen.
D.
By tem|X)rarily relieving the symptoms of asthma, inhalers encourage sufferers to avoid more beneficial measures.
E.
Ten years ago bronchial inhalers were not available as an asthma treatment.