Collect Like Terms and Then Arrange in Descending Order $-3 x^{5}+3 x^{6}+9 x+9 x^{6}+8 x+6 x^{5}$

Multiple Choice

Collect like terms and then arrange in descending order.
- $-3 x^{5}+3 x^{6}+9 x+9 x^{6}+8 x+6 x^{5}$

A) $12 x+3 x^{6}+17 x^{5}$
B) $11 x^{6}+6 x^{5}+15 x$
C) $12 x^{6}+3 x^{5}+17 x$
D) $32 x^{12}$