Option 1 states that the capital of South Sudan is Juba. This statement is correct. Juba has been the capital city of South Sudan since its independence in 2011.

Option 2 claims that South Sudan is Africa’s first post-colonial nation. This statement is incorrect. South Sudan is not Africa`s first post-colonial nation. Several African countries achieved independence before South Sudan, such as Ghana, which gained independence from British colonial rule in 1957.

Option 3 states that India has stationed peacekeepers in South Sudan. This statement is correct. India has sent peacekeeping forces to South Sudan as part of the United Nations Mission in South Sudan (UNMISS). These peacekeepers are deployed to maintain peace and stability in the country.

Option 4 suggests that the Nile flows through Sudan, then South Sudan, and finally into Egypt. This statement is incorrect. The Nile indeed passes through Sudan before reaching Egypt, but it does not flow through South Sudan. South Sudan is located to the east of Sudan, and the Nile does not run through its territory.

In conclusion, option 4 is incorrect as it inaccurately describes the flow of the Nile through South Sudan.