The pathophysiology of type 1 diabetes can best be described as:

Choice A reason: Cataract development is a common issue in people with diabetes due to the high blood sugar levels that affect the lens of the eye. However, it is not the primary cause of visual impairment. Cataracts cause the lens to become cloudy, leading to blurred vision, but the impact is generally less severe compared to the microvascular complications of diabetes.

Choice B reason: Exophthalmos, or bulging of the eye, is not typically associated with diabetes. It is more commonly seen in conditions like Graves' disease, an autoimmune disorder affecting the thyroid. Therefore, while it is important to be aware of various conditions that can impact eye health, exophthalmos is not a primary complication of diabetes.

Choice C reason: Abnormal metabolism in the lens can contribute to the formation of cataracts, but it is not the main reason for diabetic visual impairment. The primary issue in diabetes-related visual impairment is damage to the small blood vessels in the retina, not just changes in the lens metabolism.

Choice D reason: Microvascular changes in the eye, particularly diabetic retinopathy, are the primary cause of visual impairment in people with diabetes. High blood sugar levels can damage the blood vessels in the retina, leading to leakage, swelling, and the formation of new, abnormal blood vessels. This can result in significant vision loss and even blindness if not properly managed. Regular eye examinations and control of blood glucose levels are crucial in preventing and managing diabetic retinopathy.

Choice A reason: While white blood cells (WBC) are essential for fighting infections, increased WBCs in the blood is not the reason why a minor injury can cause major complications in individuals with diabetes. In fact, diabetes can impair the function of WBCs, making it harder to fight infections.

Choice B reason: Edema, or swelling, can occur in individuals with diabetes, especially in the lower extremities. However, it is not the primary reason why minor injuries can lead to severe complications. Edema can contribute to discomfort and further complications, but it is not the root cause.

Choice C reason: Increased blood flow and oxygen delivery to tissues would generally be beneficial for healing. However, individuals with diabetes often have impaired blood flow, not increased blood flow. This impairment can hinder the healing process and lead to complications.

Choice D reason: The major reason why a minor injury can cause significant complications in individuals with diabetes is due to decreased blood flow to the tissues. Diabetes can cause damage to blood vessels and nerves (peripheral neuropathy), leading to poor circulation and a reduced ability to sense injuries. This decreased blood flow can prevent adequate delivery of oxygen and nutrients to the tissues, leading to slow healing, increased risk of infection, and in severe cases, gangrene (tissue death). Without proper blood flow, even minor injuries can become serious and may require medical intervention, including possible amputation to prevent the spread of infection.