Interesting facts from India (Serial No. 1):

-Political Parties are NOT public authorities! (http://www.indianexpress.com/news/change-in-rti-act-gets-cabinet-nod-parties-exempted/1150156/), so they are exempt from RTI!

-But Donation to Political Parties is 100% Tax Exempt! (http://80g.in/), for NGOs it is only 50%. All other entities that get 100% exemptions are only "National Funds". Based on point-1 above, why 100% exemption is being given for "non-public" authorities?
So that the information does not get lost - copying-pasting here for ready reference:

100% and 50% Deductions

National Funds (100%)

1. Nationla Defence Fund
2. Prime Minister's National Relief Fund
3. Prime Minister's Armenia Earthquake Relief Fund
4. Africa (Public Contributions-India) Fund
5. National Foundation for Communal Harmony
6. Approved university/educational institution
7. Chief Minister's Earthquake Relief Fund
8. Zila Saksharta Samiti
9. National Blood Transfusion Council
10. Medical Relief Funds of state govt
11. Army Central Welfare Fund, Indian Naval Ben. Fund, Air Force Central Welfare Fund.
12. National Illness Assistance Fund
13. Chief Minister's or Lt. Governor's Relief Fund
14. National Sports Fund
15. National Cultural Fund
16. Govt./ local authority/ institution/ association towards promoting family planning
17. Central Govt.'s Fund for Technology Development & Application
18. National Trust for Welfare of Persons with Autism, Cerebral Palsy, Mental Retardation & Multiple Disabilities
19. Indian Olympic Association/ other such notified association
20. Andhra Pradesh Chief Minister's Cyclone Relied Fund

Political Parties (100%)

1. BJP
2. Congress
3. CPM
4. BSP
5. SP
6. CPI

NGO Charities (50%)

1. Jawaharlal Nehru Memorial Fund
2. Prime Minister's Drought Relief Fund
3. National Children's Fund
4. Indira Gandhi Memorial Trust
5. Rajiv Gandhi Foundation
6. Donations to govt./ local authority for charitable purposes (excluding family planning)
7. Authority/ corporation having income exempt under erstwhile section or u/s 10(26BB)
8. Donations for repair/ renovation of notified places of worship
9. World Vision India
10. Udavum Karangal