How did Michael Corleone know it was Carlo Rizzi?

How did Michael Corleone know that Carlo Rizzi was the traitor who had set up Sonny Corleone? In the Godfather, the one event that completely changed the paradigm of the Corleone family’s fight for supremacy, was the trap placed for the acting don, Sonny Corleone. There was someone within the family that had conspired to have him taken out, a traitor. However after years of rebuilding, Michael finally confronts this traitor after years of putting them at ease, giving them a false sense of security. As we all know, this traitor was Carlo Rizzi. So the question that we all have been wondering, is how did Michael know, Although we can assume that he concluded that he saw through that. However, upon looking into this further, it’s actually not as simple or clear as we all thought, rather was actually quite shocking…. At the height of the 5 families war, Carlo betrayed the Corleone family and played a crucial role in taking out the acting boss, Santino Corleone, Shifting the balance of power i