**Core Concept**
Elevated serum ferritin levels, coupled with decreased serum iron and % transferrin saturation, point towards an iron overload state, specifically one that is not due to iron deficiency anemia. This profile suggests an accumulation of iron within the body, potentially due to increased absorption, decreased excretion, or chronic inflammation.

**Why the Correct Answer is Right**
The correct answer is associated with increased iron stores, which can be seen in conditions like hemochromatosis, where there is excessive absorption of dietary iron. However, in this scenario, we are looking for a diagnosis that is not due to iron deficiency anemia. The presence of elevated ferritin levels indicates an increase in stored iron, which is then reflected in decreased serum iron and % transferrin saturation due to its sequestration. This profile is most consistent with iron overload states, such as hemochromatosis or iron overload due to chronic transfusions.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because iron deficiency anemia is characterized by decreased serum ferritin levels, not elevated levels.
**Option B:** This option is incorrect because anemia of chronic disease typically presents with decreased serum iron and % transferrin saturation, but with normal or elevated serum ferritin levels due to inflammation-induced hepcidin production. However, the combination of decreased serum iron and % transferrin saturation with elevated ferritin levels is more indicative of iron overload.
**Option C:** This option is incorrect because hemosiderosis refers to the accumulation of iron in tissues, but it does not specifically account for the laboratory findings of decreased serum iron and % transferrin saturation.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that elevated serum ferritin levels can be seen in a variety of conditions, including iron overload, inflammation, and malignancy. However, the combination of decreased serum iron and % transferrin saturation with elevated ferritin levels is highly suggestive of iron overload states.

**Correct Answer:** D.