Answer:
1. Aggregation.
2. Composition.
3. Inheritance.
4. Association.
Explanation:
In object-oriented programming (OOP) language, an object class represents the superclass of every other classes when using a programming language such as Java.
The four (4) main types of relationship and their object-oriented programming (OOP) concept includes;
1. Aggregation: has-a relationship, where one class has an object of another.
2. Composition: a relationship where we define one class as private inside another.
3. Inheritance: is a relationship, where we derive one class from an existing class.
4. Association: a relationship, where one class uses the other.