You Purchase a 30-Year,zero-Coupon Bond for a Price of $20

You purchase a 30-year,zero-coupon bond for a price of $20.The bond will pay back $100 after 30 years and make no interim payments.The annual compounded return (geometric average return) on this investment is:

A) 5.31%
B) 6.54%
C) 4.78%
D) 5.51%