MrAllenby,77 Years Old,experiences Frequent Urination at Night

Mr.Allenby,77 years old,experiences frequent urination at night.Except for a diuretic he takes once per day for hypertension,he is otherwise healthy.How would the nurse explain the reason for his nocturia to Mr.Allenby?

A) Decrease in bladder capacity increases frequency of urination
B) Expected effect of the diuretic
C) Decrease in the number of nephrons
D) Increase in cardiac output