10 Suspects and Police

10 suspects are rounded by the police and questioned about a bank robbery. Only 1 of them is guilt. The suspects are made to stand in a line& each person declares that the person next to him on his right is guilty. The right most person is not questioned. Which of the following possibilities are true
A. all suspects are lying or the leftmost suspect is innocent
B. all suspects are lying and the leftmost suspect is innocent
(a) A only (b) neither A nor B (c) B only (d) both a & b