Renal papillary necrosis is almost always associated with one of the following conditions :
Answer is A (Diabetes Mellitus): `Renal papillary necrosis, an accompaniment of acute pyelonephritis is most often seen in diabetics and is characterised by necrosis of renal papillae of one or both kidneys with sharped demarcation between necrotic and living tissue' -- Dorlands Thus while papillary necrosis is a feature of more than one conditions mentioned in the question, it is most commonly seen with diabetes mellitus.
Diabetes-mellitus
Analgesic-nephropathy
Chronic pyelonephritis
Post streptococcal GN