\({x^2} - 9x - 9y - {y^2}\)

Câu hỏi: \({x^2} - 9x - 9y - {y^2}\)

A \(\left( {x + y} \right)\left( {x - y - 9} \right)\)       

B \(\left( {x - y} \right)\left( {x + y - 9} \right)\)     

C \(\left( {x + y} \right)\left( {x + y + 9} \right)\)    

D \(\left( {x - y} \right)\left( {x + y + 9} \right)\)