Question about classes [will specify once I know what the name of what I'm looking for is]

Let's say I've got a class,

 public class Base{
     public int data;
 }

two subclasses

 public class A : Base{
     public int aType_Data;
 }  
 
 public class B : Base{
     public int bType_Data;
 }

and a function

 public void getData(common_type){
     Debug.Log("Basic data: " + data);
 }

that has to be able to receive both an A object or a B object, but only has to access the variables that belong to the base class, "Base". Is there any way to have a single function with a single argument that can be any of the two subclasses?