**Core Concept**
Immune thrombocytopenic purpura (ITP) is an autoimmune disorder characterized by the production of antibodies against platelet antigens, leading to platelet destruction and a decrease in platelet count.

**Why the Correct Answer is Right**
ITP is indeed an autoimmune disease where autoantibodies against platelet glycoproteins (notably GPIIb/IIIa) are produced by B cells, marking platelets for destruction by the spleen. This process results in a low platelet count (thrombocytopenia). **Option A** correctly identifies the pathophysiological mechanism underlying ITP. The correct answer also involves recognizing that platelet production is actually suppressed in ITP, not increased, making **Option C** incorrect.

**Why Each Wrong Option is Incorrect**
**Option B:** Massive splenomegaly is not a characteristic feature of ITP. Splenomegaly can occur due to other causes, but in ITP, the spleen is often not palpable.
**Option D:** I.V. immunoglobulin (IVIG) is actually a treatment for ITP, used to increase platelet count by saturating the Fc receptors of macrophages in the spleen, thus reducing platelet destruction.
**Option E:** Chronic ITP is not self-limiting and often requires long-term management, including medications to suppress the immune system and/or replace platelets.

**Clinical Pearl / High-Yield Fact**
IVIG is a useful treatment for ITP, but its mechanism of action is not fully understood and may involve interference with the function of Fc receptors on macrophages.

**Correct Answer:** A. Autoimmune mediated