Answer: B. Jim's need to justify the effort he put into his training has altered his attitude to be more favourable toward the job
Explanation: A rational analysis would probably lead Jim to find out that it is better not to do a job that he does not love, despite his time spent studying for that job, but also, maybe that same analysis would lead him to realise that it is better to do something than do it again study, invest new time for learning, etc.
Jim simply saw all the facts, realised that he had spent years learning for the job and now wants to justify the effort he has put into it. Therefore, he changed his attitude towards the job.