Correct Option: C

protocol protocol (N.) : a system of fixed rules and formal behaviour used at official meetings, usually between governments formality (N.) : a thing that you must do as a formal/official part of a legal process, a social situation, etc. statesmanship (N.) : skill in managing state affairs hierarchy (N.) : a system, in a society/an organisation, in which people are organised into different levels of importance from highest to lowest