I don't think you will find anything safe that will give you anywhere close to the return you want.
12% is a fairly high return which no safe option will give you.
You can invest in mutual funds and can most probably get 12% return in long term but it's not a safe guaranteed return.
Safe investment will always be under 10% that too for super senior citizens and anything above that (10%) will be risk investment only, so for safe investment currently its Suryoday Bank which gives 9.01% (9.25% for senior folks) for 5yrs FD meaning 3.2L invested for 5yrs fetches 5L (11.23% annualized/ for senior citizen close to 11.5% annualized), the reason for 3.2L is for 5L insurance coverage by DICGC