Simplify the following expression: $(9x^9+7x^8+4x^7) + (x^{11}+x^9+2x^7+3x^3+5x+8).$ Express your answer as a polynomial with the degrees of the terms in decreasing order.
(A)x^{11}+2x^9+2x^8 (B)x^{11}-6x^8+6x^7+3x^3+5x+8 (C)x^11 + 10x^9 + 7x^8+6x^73x^3+5x+8 (D)x^{11}+10x^9+7x^8+6x^7+3x^3+5x+8
D