Jack Robs a Convenience Store

Multiple Choice

Jack robs a convenience store.He flees the scene and goes to his twin brother Mack's home.Jack tells Mack that he has robbed a store and needs to hide out for a few days.Mack agrees for Jack to stay at his house.Three days later,police officers arrive.Jack escapes out the back window but the officers arrest Mack.Mack may rightfully be convicted of:

A) robbery because he allowed Jack to hide out in his home.
B) robbery because he knew Jack robbed the store and made no effort to notify the police.
C) no offense because he engaged in no criminal conduct himself.
D) some appropriate offense related to providing post-crime assistance to Jack.