Which polynomial correctly combines the like terms and expresses the given polynomial in standard form? 8mn^5 – 2m^6 + 5m^2n^4 – m^3n^3 + n^6 – 4m^6 + 9m^2n^4 – mn^5 – 4m^3n^3 a. n^6 + 7mn^5 + 14m^2n^4 – 5m^3n^3 – 6m^6 b. –2m^6 – 5m^3n^3 + 14m^2n^4 + 7mn^5 + n^6 c. 14m^2n^4 + 7mn^5 – 6m^6 – 5m^3n^3 + n^6 d. n^6 – 6m^6 + 7mn^5 + 14m^2n^4 – 5m^3n^3