Answer:
"George kills Lennie by shooting him in the back of the head to save him from a more painful death at the hands of Curley, who has vowed to make him suffer for the death of his wife."
"Curley ends up finding out Lennie killed his wife and wants to torture and then kill Lennie. George doesn't want Lennie to suffer so George kills Lennie instantly. ... Lennie is at fault for his own death because George specifically told him not to talk to Curley's wife."
Step-by-step explanation: