A Soft Drink Company Holds a Contest in Which a Prize

Multiple Choice

A soft drink company holds a contest in which a prize may be revealed on the inside of the bottle cap. The probability that each bottle cap reveals a prize is 0.26, and winning is independent from one bottle to the next. You plan to keep buying bottles until you win a prize. Let X be the number of bottles you purchase.
-What is the expected value of the number of bottles you will need to purchase until you win a prize?

A) 1.56
B) 2
C) 3.85
D) 4