f(x)=x^2-4/x^2-9 what describes the end behavior of the function.
A. The function approaches 0 as x approaches -infinity sign and infinity sign.
B. The function approaches 9/4 as x approaches -infinity sign and infinity sign.
C. The function approaches as 2/3 x approaches -infinity sign and infinty sign.
D. The function approaches 1 as x approaches -infinity sign and infinity sign .