Calculus

Let r(x) = tan?(x). Which of the following best describes its fundamental algebraic structure? A. A composition f(g(x) ) of basic functions B. A sum f(x) + g(x) of basic functions C. A product f(x) . g(x) of basic functions D. A quotient f (x) /g(a) of basic functions where f ( ac ) = g(2) =