How to pass this by ref in C#?

Question

In a class (ClassA) of mine I want to create a related instance of another class (ClassB) providing it with a reference to the object who has initiated it\'s creation. So I\

Answer 1

You can't change the this pointer, which is something that the ref keyword allows. Why can't you declare ClassB like this?

ClassA m_classA;
public ClassB(ClassA classA)
{
   m_classA = classA;
}