Which data model focuses on objects and their interactions as the primary design element?

The object-oriented model is centered around the concept of "objects" as its fundamental building blocks, where an object represents an instance of a class that encapsulates both data and the methods to manipulate that data. This model emphasizes not only the structure of data but also the relationships and interactions between different objects.

By organizing data into objects, it allows for a more intuitive mapping to real-world entities. The interactions between these objects, which can include inheritance and polymorphism, facilitate complex behaviors in software applications. This design approach is particularly beneficial in programming languages that are object-oriented, making it easier to develop and manage software systems that reflect real-world systems and processes.

In contrast, other data models, such as the relational model, hierarchical model, and network model, focus on the relationships and structure of data without encapsulating behavior directly within the data entities. The relational model organizes data in tables, emphasizing relationships through keys. The hierarchical model organizes data in a tree-like structure, and the network model utilizes more complex relationships but does not manage behavior and interactions as the main focus. Thus, the object-oriented model stands out by prioritizing both data and behavior, making it the correct choice for this question.