ओजोन छिद्र (Ozone hole) मुख्य रूप से किस महाद्वीप के ऊपर पाया जाता है?

The 'Drain of Wealth' theory was propounded by which Indian nationalist leader?

Which event is considered the turning point in Mahatma Gandhi's leadership in the Indian independence movement?

Which African leader is known for his non-violent opposition to colonial rule?