निम्नलिखित में से कौन सा एक जल प्रदूषक (विषैली भारी धातु) है?

Which of these leaders did not lead any major movement *independently* for Indian independence, primarily participating under the leadership of others?

Which of the following events is considered the most direct cause for the end of British rule in India?

The first war of Indian independence began in the year __________.

Who among the following was NOT a member of the Simon Commission?

Who among the following is known for presiding over the Karachi session of the Indian National Congress in 1931, which is significant for its resolution on Fundamental Rights and Economic Policy?