All of the following are modifiable risk factors for falls EXCEPT

A. History of stroke: A prior stroke represents a fixed neurologic event that cannot be altered. While rehabilitation can improve function, the underlying history of stroke itself remains a non-modifiable risk factor for falls due to persistent deficits such as weakness or impaired balance. B. A high basal insulin dose of Lantus every evening: Insulin dosing can be adjusted to reduce the risk of nocturnal or early-morning hypoglycemia, which increases fall risk. Medication review and dose modification make this a modifiable factor. C. Low vitamin D levels: Vitamin D deficiency can be corrected with supplementation, improving muscle strength and balance. Addressing low vitamin D has been shown to reduce fall risk in older adults. D. Morphine use for Parkinson's Disease: Opioids increase fall risk through sedation, dizziness, and impaired coordination. Medication choice, dosing, or discontinuation can be modified to reduce this risk.