Final answer:
Arthur is liable because he is not free to inflict intentional injury on a trespasser.
Step-by-step explanation:
In this scenario, Arthur decides to put a strong electric shock system on his front door's doorbell to prevent religious representatives from preaching to him despite him having signs around his home saying 'No solicitors'. The question asks who is liable for Arthur's actions.
The correct answer is A. Arthur is liable because he is not free to inflict intentional injury on a trespasser. While Arthur may have the right to prevent trespassing solicitors by any means possible, intentionally causing harm to another person, even if they are trespassing, is generally not permitted under the law. It is important to respect the rights and safety of others, even if we disagree with their actions or beliefs.