How did Sultan Qutb-ud-din Aibak die ?

• A. He was treacherously stabbed to death by one of his ambitious nobles
• B. He was killed in a battle with Taj-u-din Yildiz, the ruler of Ghazni who entered into a contest with him over the capture of Punjab
• C. He sustained injuries while besieging the fortress of Kalinjar in Bundelkhand and succumbed to them later
• D. He died after a fall from his horse while playing chaugan