In this scene, George and Lennie are eating before meeting their boss and George tells Lennie that he wants him to stay with him when Lennie said that he can go if George wanted him to. This relates to plot development because George is willing to be with him.
In this scene, George is backing up Lennie when Curly puts him on the spot for being tall, calling him "big guy." This relates to plot development because as a friend, it is naturally to back up a friend.
In this scene, Carlson is complaining about how Candy's dog smells bad and how it is all old and rusty. Candy doesn't notice his smell saying he has had him for a long time. This relates to plot development because Candy shows that he has gotten used to him while time went by while being with his dog all the time.
In this scene, Crook asks Lennie, "suppose George doesn't come back?" and Lennie gets mad saying, "What you supposin' for? Ain't nobody goin' to suppose no hurt to George." This relates to the plot development because Lennie is worrying about George and getting mad.
In this scene, Curly's wife tries to have a conversation with him and Lennie says he wants to pet rabbits and she calls him nuts but he says george doesn't think he is nuts. This relates to the plot development because he trusts George's words.
In this scene, George and Lennie tell eachother that they will always be together and will still get that house. This relates to plot development because Lennie thinks they will always be together. and trusts George.