AHSME 1960 Problem 9

The fraction $\frac{a^2+b^2-c^2+2ab}{a^2+c^2-b^2+2ac}$ is (with suitable restrictions of the values of a, b, and c): $\text{(A) irreducible}$ $\text{(B) reducible to negative 1}$ $\text{(C) reducible to a polynomial of three terms}$ $\text{(D) reducible to} \frac{a-b+c}{a+b-c}$ $\text{(E) reducible to} \frac{a+b-c}{a-b+c}$