Leonard spent several years in the Warsaw Ghetto before being put on a train to Treblinka. Upon arriving at Treblinka, Leonard is singled out from the rest. He is put to work, splitting stones that are used to build roads. Just before Treblinka is liquidated, Leonard is sent to another camp. He manages to survive the war. Leonard begins building a new life for himself. Still, every day, guilt hangs over him. What is MOST likely the reason for Leonard’s feelings?