## Core Concept
Diabetes Mellitus (DM) is a chronic metabolic disorder characterized by high blood glucose levels due to defects in insulin secretion, insulin action, or both. It is broadly classified into Type 1 Diabetes Mellitus (T1DM) and Type 2 Diabetes Mellitus (T2DM), with distinct pathophysiological mechanisms. Understanding the differences between these types and their management strategies is crucial.

## Why the Correct Answer is Right
The correct answer cannot be directly evaluated without the specific statements provided in the question. However, generally speaking, statements about Diabetes Mellitus being true would involve its pathophysiology, diagnosis, and management. For instance, T1DM is characterized by autoimmune destruction of pancreatic beta cells leading to absolute insulin deficiency. T2DM is associated with insulin resistance and impaired insulin secretion. The management of DM involves lifestyle modifications, oral hypoglycemic agents, and insulin therapy, tailored to the type and severity of diabetes.

## Why Each Wrong Option is Incorrect
- **Option A:** Without the specific statement, it's challenging to provide a direct explanation. However, if a statement claims that Type 1 Diabetes Mellitus is caused by insulin resistance, it would be incorrect because T1DM is primarily due to autoimmune beta-cell destruction.
- **Option B:** If a statement suggests that all diabetic patients require insulin therapy, it would be incorrect because not all patients with diabetes need insulin; management depends on the type of diabetes, its severity, and the patient's response to other treatments.
- **Option C:** If a statement posits that Diabetes Mellitus is solely a disorder of carbohydrate metabolism, it would be incorrect because DM affects not only carbohydrate but also protein and fat metabolism.
- **Option D:** Similarly, without specifics, if a statement claims that the only complication of diabetes is nephropathy, it would be incorrect because diabetes can lead to a wide range of complications including retinopathy, neuropathy, cardiovascular disease, and more.

## Clinical Pearl / High-Yield Fact
A crucial point to remember is the **ABCD** of diabetes management: **A**ssessing cardiovascular risk, **B**lood pressure control, **C**holesterol management, and **D**iabetes self-management education. Early detection and management of diabetes and its complications are critical.

## Correct Answer: D.