Final answer:
Relationships between different ranks can be prohibited based on historical aristocratic laws, military regulations, and religious discrimination within the context of separation of church and state.
Step-by-step explanation:
Relationships between different ranks are prohibited in various contexts ranging from historical societal structures to modern military guidelines. Historically, in aristocratic societies, there were intricate ranking systems within families and the larger society. Remarrying across ranks contravened laws, and children would inherit the lower status of the two parents. Military regulations have also addressed relationships between ranks. For example, Defense Directive 1304.26 was a policy that prohibited discrimination in the military but did not allow non-heterosexual individuals to serve openly until it was repealed. Relationships between different ranks in the military are often discouraged or outright forbidden to maintain discipline and order.
Moreover, religious discrimination can play a role in prohibiting relationships, often within the context of laws that encompass the separation of church and state. In these cases, relationships are sometimes regulated to prevent the improper fusion of religious and governmental influence.