Find the derivative of the function r(t) = ((5t - 7)^6) / (4t^2 + 3). What is the derivative of r(t)?
A) 6(5t - 7)^5 / (4t^2 + 3)
B) (6(5t - 7)^5 - 8t(5t - 7)^6) / (4t^2 + 3)^2
C) (6(5t - 7)^5 - 8t(5t - 7)^6) / (4t^2 + 3)
D) (6(5t - 7)^5 - 8t(5t - 7)^6) / (4t^2 + 3)^2