**Core Concept**
Hereditary spherocytosis (HS) is a genetic disorder characterized by the production of abnormal, sphere-shaped red blood cells. This condition arises due to mutations affecting the cytoskeletal proteins of the red blood cell membrane, leading to membrane instability and premature destruction.

**Why the Correct Answer is Right**
The correct answer is related to spectrin, a critical cytoskeletal protein that maintains the shape and stability of the red blood cell membrane. A defect in spectrin leads to a reduction in membrane surface area, resulting in spherocytic red blood cells that are prone to hemolysis. Spectrin is composed of two subunits, alpha and beta, and mutations in either of these subunits can cause HS.

**Why Each Wrong Option is Incorrect**
**Option A:** Glycophorin C is a transmembrane protein involved in red blood cell membrane structure, but defects in glycophorin C are associated with MNS blood group system abnormalities, not hereditary spherocytosis.
**Option B:** Ankyrin is another cytoskeletal protein that interacts with spectrin and the red blood cell membrane, but defects in ankyrin are associated with a different form of HS.
**Option C:** Band 3 is an integral membrane protein involved in anion exchange, but defects in band 3 are associated with other forms of hemolytic anemia, not hereditary spherocytosis.

**Clinical Pearl / High-Yield Fact**
Hereditary spherocytosis can be diagnosed by performing a peripheral smear to identify spherocytic red blood cells and by demonstrating increased osmotic fragility of red blood cells in a laboratory setting.

**Correct Answer: A. Spectrin.**