Final answer:
In a relational database, each type of entity should be represented by a separate table. The correct answer is D. All of the above.
Step-by-step explanation:
In a relational database, each type of entity should be represented by a separate table. This helps organize the data and maintain data integrity. Based on the given options, resources, events, and agents should all be separate tables in a relational database. Therefore, the correct answer is D. All of the above.
When designing a relational database, several types of entities might need to be represented as separate tables. In this context, a 'resource' refers to an item or valuable data, an 'event' signifies a change or occurrence in the system, and an 'agent' is an actor or entity that can perform actions. Consequently, each of these entity types should typically be stored in separate tables within a relational database structure for normalization and to maintain data integrity, thereby making option D (All of the above) the correct answer.