Both statements in the given question are individually true.

Statement I states that the Kisan manifesto adopted by the All India Kisan Sabha in August 1936 contained radical demands. This is accurate because the Kisan manifesto did indeed contain radical demands to address the issues faced by farmers in India during that time. The demands included the abolition of the zamindari system, rent reduction, and reduction in land revenue.

Statement II claims that the All India Kisan Sabha was a part of the Congress and maintained close relationships with the Provincial Congress Committees. This is also true. The All India Kisan Sabha was established in 1936 and was affiliated with the Indian National Congress. They worked closely with Congress and its committees at the provincial level to advocate for the rights and demands of farmers.

Option 2 correctly states that both statements are individually true, but Statement II is not the correct explanation of Statement I. Even though the All India Kisan Sabha had a relationship with the Congress, it does not necessarily mean that this relationship is the explanation for the radical demands in the Kisan manifesto. The radical demands in the manifesto were a result of the issues faced by farmers during that time, and the All India Kisan Sabha advocated for those demands independently.