A $50,000 investment earns 18% annually. If B represents the balance and t represents the number of years, determine an expression that gives the account balance, B, after t years. Also, determine an equivalent expression that displays the effective monthly interest rate.

A) B = 50000(1.18)t; B = 50000(1.14)^12t
B) B = 50000(1.18)t; B = 50000(1.014)^12t
C) B = 50000(1.018)t; B = 50000(1.14)^12t
D) B = 50000(1.18)t; B = 50000(0.014)^12t