Eight light bulbs numbered 1 through 8 are arranged in a circle. The bulbs are wired so that every third bulb, counting in a clockwise direction, flashes until all bulbs have flashed once. If the bulb numbered 1 flashes first, which numbered bulb will flash last?
(A)2
(B)3
(C)4
(D)6
(E)7
Ans:D
題目看不太懂ㄟ