Which expression represents the sixth term in the binomial expansion of (5y + 3)10?

Which expression represents the sixth term in the binomial expansion of (5y + 3)10?

A. 10C5(5y)5(3)5
B. 10C6(5y)4(3)6
C. 510C5(y)5(3)5
D. 510C6(y)4(3)6