What is the sum?

(g² – 4g⁴ + 5g + 9) + (–3g³ + 3g² – 6)

A. –7g⁴ + 4g³ – 3g² + 5g – 3
B. –4g⁴ – 3g³ + 4g² + 5g + 3
C. –4g⁴ + 4g² + 14g – 6
D. –3g⁴ + 14g – 6