Quy đồng mẫu thức hai phân thức: x+y / x^2 y +x^2 ; 2x-y /y+1

A. $\frac{x-y}{x^{2}y+x^2}=\frac{x-y}{x^2(y+1)};\frac{2x+y}{y+1}=\frac{x^2(2x-y)}{x^2(y+1)}$ 

B. $\frac{x+y}{x^{2}y-x^2}=\frac{x+y}{x^2(y-1)};\frac{2x-y}{y+1}=\frac{x^2(2x-y)}{x^2(y+1)}$

C. $\frac{x+y}{x^{2}y+x^2}=\frac{x+y}{x^2(y+1)};\frac{2x-y}{y+1}=\frac{x^2(2x-y)}{x^2(y+1)}$ 

D. $\frac{x+y}{x^{2}y+x^2}=\frac{x+y}{x(y+1)};\frac{2x-y}{y+1}=\frac{2x-y}{x^2(y+1)}$