Let \(f_{1}(s)=e^{x}, f_{2}(x)=e^{f(x)}, \ldots \ldots . f_{n+1}(x)=e^{f(x)}\) for all \(n \geq 1\). The for any fixed \(n, \frac{d}{d x} f_{n}(x)\) is
(A) \(f_{n}(x)\)
(B) \(f_{n}(x) f_{n-1}(x)\)
(C) \(f_{n}(x) f_{n-1}(x) \ldots . f_{1}(x)\)
(D) \(f_{n}(x) \ldots \ldots \ldots f_{1}(x) e^{x}\)