**Core Concept**
The crescent formation in glomerular diseases is a hallmark of severe, aggressive glomerulonephritis characterized by the proliferation of parietal epithelial cells and macrophages within Bowman's space. This process leads to the formation of a crescent-shaped structure that can cause significant glomerular damage and impairment of renal function.

**Why the Correct Answer is Right**
Rapidly progressive glomerulonephritis (RPGN) is an aggressive glomerular disease characterized by the rapid decline in renal function, often within weeks or months. The crescent formation in RPGN is a result of the intense immune response and the subsequent activation of the coagulation cascade, leading to the deposition of fibrin and the proliferation of parietal epithelial cells within Bowman's space. This process is mediated by the production of various cytokines and chemokines, including tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1β). The crescent formation in RPGN can lead to the disruption of the glomerular filtration barrier, resulting in significant proteinuria and hematuria.

**Why Each Wrong Option is Incorrect**
**Option A:** Minimal change disease is characterized by the loss of foot processes in the glomerular basement membrane, but it does not typically exhibit crescent formation. Instead, it presents with nephrotic syndrome due to massive proteinuria.
**Option C:** Focal and segmental glomerulosclerosis (FSGS) is a common cause of nephrotic syndrome, but it does not typically exhibit crescent formation. FSGS is characterized by the scarring of glomeruli, which can lead to significant proteinuria and renal impairment.
**Option D:** The term "Rapidly non progressive glomerulonephritis" is not a recognized glomerular disease. The correct term is Rapidly progressive glomerulonephritis (RPGN), which is characterized by a rapid decline in renal function.

**Clinical Pearl / High-Yield Fact**
The presence of crescent formation in a renal biopsy is a critical diagnostic clue for rapidly progressive glomerulonephritis. However, it is essential to note that the absence of crescent formation does not rule out RPGN, as the disease can present in a non-crescentic form.

**✓ Correct Answer: B. Rapidly progressive glomerulonephritis**