Find the derivative of Tan(x) = Tan(y).

• A. \(\frac{1+x^2}{1+y^2}\)
• B. \(\frac{1+y}{1+x^2}\)
• C. \(\frac{1+y^2}{1+x^2}\)
• D. \(\frac{1+y^2}{1+x}\)