Find ( frac{dy}{dx} ), if x=6 sin-1 2t and y= ( frac{1}{ sqrt{1-4t^2}} ).

• A. ( frac{t}{1-4t^2} )
• B. ( frac{1}{3(1-4t^2)} )
• C. ( frac{t}{3(1-4t^2)} )
• D. ( frac{1}{3(1-4t^2)} )