Hi!
Positive connotation would be words that are uplifting, or just, positive.
Fired, isn't a very positive word, because we normally think of "YOU'RE FIRED" or a gun shooting when we hear it.
Canned isn't a positive word because it can be used like "he was canned from his job last week.".
Retired is positive, because normally people are excited to retire and move on with their life, because they're tired of their job.
The answer is retired.
Hope this helps! :)
