Simplify the product.
5a² (3a^4 + 3b + 2)

A. 8a^4 + 8ab + 5a²
B. 15a^8 + 3b + 10a²
C. 15a^6 + 15a²b + 10a²
D. 89^6 + 15a²b + 5a²