If a=xx+ya=xx+y and b=yx−y,b=yx−y, then aba+baba+b is equal to = ?

• A. xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyxyxyxyx2+y2x2+y2x2+y2x2x2x2x2xx22+y2y2y2y2yy22xyx2+y2
• B. x2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2xyx2+y2x2+y2x2+y2x2x2x2x2xx22+y2y2y2y2yy22xyxyxyxyx2+y2xy
• C. xx+yxx+yxx+yxx+yxx+yxx+yxx+yxx+yxx+yxx+yxxx+yx+yx+yx+yxx+y
• D. (yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)2(yx+y)(yx+y)((yx+yyx+yyx+yyx+yyyx+yx+yx+yx+y))22(yx+y)2