Answer:
The killers who choose poison for killing the victim are the one who does not want to confront the victim. When a knife or a bullet is used to kill a person he may struggle and can cause harm to killer also.
Step-by-step explanation:
Poison is the most easiest way to kill a person without any struggle. The poison can be given to a person in a juice or through an injection. The poison entered in the body of victim will cause his heart to cease gradually and he will not have energy to struggle with the killer to save his life.