Model Definition: The Black-Scholes PDE governs the price V(S,t) of a European option: ∂V/∂t + ½σ²S²∂²V/∂S² + rS∂V/∂S − rV = 0. Its closed-form solution yields Greeks that quantify sensitivity to each market parameter: Δ (spot), Γ (convexity), Θ (time decay), ν (volatility), ρ (rates).