**Core Concept**
Nephrotic syndrome is a clinical disorder characterized by massive proteinuria (>3.5 g/1.73 m^2/day), hypoalbuminemia, hyperlipidemia, and edema. It is often caused by primary renal diseases, but can also be secondary to systemic diseases that affect the kidney.

**Why the Correct Answer is Right**
Nephrotic syndrome can be caused by various systemic diseases, including diabetes mellitus, systemic lupus erythematosus (SLE), amyloidosis, and multiple myeloma. These diseases can lead to renal damage and proteinuria. However, some systemic diseases are less likely to cause nephrotic syndrome or are not typically associated with it.

**Why Each Wrong Option is Incorrect**
**Option A:** Diabetes mellitus can cause nephrotic syndrome due to diabetic nephropathy, which is a common complication of long-standing diabetes.
**Option B:** Systemic lupus erythematosus (SLE) is a classic cause of nephrotic syndrome, particularly due to lupus nephritis, which can lead to massive proteinuria.
**Option C:** Amyloidosis can cause nephrotic syndrome due to the deposition of amyloid fibrils in the kidney, leading to renal damage and proteinuria.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that nephrotic syndrome has a wide range of causes, including primary renal diseases and systemic diseases that affect the kidney. A thorough investigation, including renal biopsy, may be necessary to determine the underlying cause.

**Correct Answer: D.**