RBI bonds for those in nil tax bracket

Simply for a Citizen of India if the total Income is upto 5 lacs he/she does not need to pay tax. In your case the Income is less than 2.5 lacs , so you can invest in these bonds as no taxability will arise in case your income is upto 5 lacs.

but you should aware that the RBI 7.75% bonds have a tenor of seven years. you can not sold before that time period and premature is not
allowed.
it's just my view on it.