Explanation:

Moplah Rebellion of 1921

• The Moplah Rebellion is a part of the Khilafat Movement led by Mahatma Gandhi and the Ali Brothers in 1921-22.
• The revolt took place in Kerala’s Malabar and involved the Moplah or Mappila Muslims of the region.
• The Malabar region consisted of Palakkad, Malappuram, Wayanad, Kasargone, Kozhikkode and Kannur which was part of the then Madras Presidency.
• Mappilah peasantry had waged revolt against the predominantly Hindu landlords of British Malabar and the colonial administration.
• The Mappilahs, under the leadership of cleric Ali Musliyar and Variyam Kunnath Kunjahammed Haji (V K Haji), captured the taluks of Eranadu and Valluvanadu from the British and established their own rule.
• After a short period, the British suppressed the rebellion.
• Mahatma Gandhi distanced himself from the rebels as they engaged in communal violence against the Hindus.
• Wagon Tragedy: In November 1921, 67 Moplah prisoners were killed when they were being transported in a closed freight wagon from Tirur to the Central Prison in Podanur. They died of suffocation. This event is called the Wagon Tragedy. the Hindu landlords.

Hence option 3rd is correct.