"He pushed the plunger very slowly, injecting the liquid into the scalp vein until the syringe was empty." Keeping this scene the same was effective because it tells the readers what "release" is. Without this scene in the book or the play, nobody would know what release is.
"He killed it! My father killed it! Jonas said to himself, stunned at what he was realizing. He continued to stare at the screen numbly." Keeping this scene the same in the book and the play was effective because it shows how release angers Jonas very much.
"His father loaded the carton containing the body into the chute and gave it a shove. "Bye-bye, little guy, Jonas heard his father say before he left the room. Then the screen went blank." Not keeping this scene in the play was not effective because in the book, it is very clear how they get rid of the babies, but in the play it is not clear since they did not include this scene.