Mostly president's of a country
I think the answer is Special Power of Attorney, it is an authority given to another person of the accountable person (principal) to act on behalf his absence for a transaction. At times this happens when a someone gets too busy of attending to every task.
Well, look at it this way, if you were selling some kind of item, you would want to establish trust, and then provide the person with information and facts about that item. You would not want to threaten the person that you are trying to sell to with any sort of language, gestures, or body language. You would want to remain calm and collective with a smile on your face. The same thing goes with online sales, you would still want to follow everything else but the last one.
So the answer is: D
