**Core Concept**
Dubin Johnson syndrome is a rare genetic disorder characterized by chronic jaundice due to an inability to secrete conjugated bilirubin into the bile. It is caused by mutations in the ABCC2 gene, leading to a deficiency of the protein known as multidrug resistance-associated protein 2 (MRP2).

**Why the Correct Answer is Right**
The key feature of Dubin Johnson syndrome is the accumulation of conjugated bilirubin in the blood, leading to jaundice. This is due to the impaired secretion of conjugated bilirubin into the bile, which is normally facilitated by MRP2. The liver cells become blackened due to the accumulation of epinephrine metabolites, giving the characteristic black liver.

**Why Each Wrong Option is Incorrect**
**Option A:**
This option is likely incorrect because Dubin Johnson syndrome is indeed characterized by chronic jaundice, which is a hallmark symptom of the disease.

**Option B:**
This option is also likely incorrect because the liver cells in Dubin Johnson syndrome do become blackened due to the accumulation of epinephrine metabolites.

**Option C:**
This option is incorrect because Dubin Johnson syndrome is caused by mutations in the ABCC2 gene, which leads to a deficiency of the protein MRP2.

**Clinical Pearl / High-Yield Fact**
One of the key distinguishing features of Dubin Johnson syndrome is the presence of a black liver, which is due to the accumulation of epinephrine metabolites. This is a crucial finding that can help in diagnosing the disease.

**Correct Answer: A.**