Find the odd one.

1. Elimination of storage of Certificates, Theft of Certificates, Torn Certificates.
Ans: Elimination of storage of Certificates

2. NSDL, CDSL, NBFC
Ans: NBFC 

3. Depository, DP, RBI.
Ans: RBI

4. DP, BO, State Government.
Ans: State Government

5. Issuer, BO, Central Government.
Ans: Central Government

6. DRF, RRF, PPF
Ans: PPF