Okay, let's tackle this question. The patient is an Rh-negative woman who had an Rh-positive fetus. The baby developed jaundice, ascites, hepatomegaly, and edema shortly after birth. These symptoms point towards hemolytic disease of the newborn (HDN), also known as erythroblastosis fetalis. The key here is understanding the pathophysiology behind the jaundice in this context.

Rh incompatibility occurs when an Rh-negative mother is exposed to Rh-positive fetal blood, usually during delivery or certain procedures. This exposure leads to the production of anti-Rh IgG antibodies in the mother. In subsequent pregnancies with Rh-positive fetuses, these antibodies can cross the placenta and attack the fetal red blood cells, causing hemolysis. The breakdown of RBCs releases bilirubin, leading to hyperbilirubinemia, which manifests as jaundice. The bilirubin is what's deposited in the skin and sclera, causing the yellow discoloration.

The question asks about the substance deposited in jaundice. The main substances involved in jaundice are bilirubin (both unconjugated and conjugated). In hemolytic jaundice, like in HDN, the primary issue is an excess of unconjugated bilirubin due to increased breakdown of RBCs. However, the bilirubin that gets deposited in tissues is typically the unconjugated form, which is lipid-soluble and can cross cell membranes to deposit in tissues, leading to the yellow staining.

Now, looking at the options (even though they're not listed here), common distractors might include things like urobilinogen, hemoglobin, or other pigments. Urobilinogen is a breakdown product of bilirubin found in urine and stool, not deposited in tissues. Hemoglobin is the oxygen-carrying protein in RBCs, but when hemolyzed, it's broken down into heme and globin. The heme part is converted to bilirubin. So hemoglobin itself isn't the deposited substance. Other options might include bilirubin conjugated, but that's water-soluble and excreted in bile, not deposited in tissues.

The clinical pearl here is that in hemolytic disease of the newborn, the jaundice is due to unconjugated hyperbilirubinemia, and the bilirubin deposits in the skin and sclera. It's important to differentiate between pre-hepatic (hemolytic), hepatic (hepatocellular), and post-hepatic (obstructive) causes of jaundice based on the type of bilirubin elevated. For exams, remembering that unconjugated bilirubin is responsible for jaundice in hemolytic conditions is key.

**Core Concept**
This question examines the pathophysiology of hemolytic disease of the newborn (HDN) due to Rh incompatibility and the biochemical basis of jaundice. The key principle involves **unconjugated bilirubin accumulation** from accelerated red blood cell (RBC) destruction in Rh alloimmunization.

**Why the Correct Answer is Right**
In Rh incompatibility, maternal anti-D IgG antibodies cross the placenta and destroy fetal Rh+ RBCs. Hemolysis

✓ Correct Answer: B. Conjugated and unconjugated bilirubin