Code of diplomatic etiquette and precedence

Answer: Option D

One word substitute is Protocol.

Statesmanship: skill in managing public affairs.
Formalism: the basing of ethics on the form of the moral law without regard to intention or consequences.
Hierarchy: a system in which members of an organization or society are ranked according to relative status or authority.
Protocol: the official procedure or system of rules governing affairs of state or diplomatic occasions.