Four children were playing baseball, and one child threw the ball at your window and broke it. Then, you went to the children and asked for the culprit.
The children answered:
A: Please do not blame me! I didn't break your window.
B: If you want to know, I broke your window.
C: Listen, A is innocent. Don't blame him.
D: My friend B didn't break that window.
You know that the culprit always lies. You also know that the others, even being innocent, can lie or tell the truth to you.
Who broke your window?