CAYLEY 1997 Problem 6

Twelve balloons are arranged in a circle as shown. Counting clockwise, every third balloon is popped, with C the first one popped. This process continues around the circle until two unpopped balloons remain. The last two remaining balloons are

Image

Answer Choices
A. B,H
B. B,G
C. A,E
D. E,J
E. F,K