दी गई श्रृंखला को तार्किक रूप से पूर्ण बनाने के लिए निम्नलिखित में से कौन सा अक्षर-संख्या समूह प्रश्न चिह्न (?) को प्रतिस्थापित करेगा? AB 10, EF 20, IJ 30, MN 40, ?

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?