Why did Mahatma Gandhi support the Khilafat Movement?

Which of the following Indian leaders did not support the Khilafat Movement?

The title given by the British Government to Mahatma Gandhi which he surrendered during the Non-Cooperation Movement was:

Who among the following, were prominent leaders of the ‘Khilafat Movement’?

Gandhiji launched the Non-Cooperation Movement in –

In which city was the conference of Khilafat Committee in 1920 held that requested Gandhiji to assume the leadership of Non-cooperation Movement?