The correct answer is for.
Imam Husayn died for a noble cause. This means that he died while fighting for something that he believed in, even though he knew that he would likely die in the process. He was willing to sacrifice his own life in order to protect his beliefs and to stand up for what he thought was right.
The other options are incorrect because they do not accurately describe Imam Husayn’s death. He did not die of a noble cause, meaning that he did not die as a result of his beliefs. He also did not die in a noble cause, meaning that he did not die while he was working towards a noble goal. Finally, he did not die at a noble cause, meaning that he did not die at the time of a noble event.
Imam Husayn’s death is a significant event in Islamic history. It is often remembered as a symbol of the importance of standing up for what you believe in, even in the face of death.