Senior citizen

Your father can Claim Medical Expenses u/s 80ddb upto Rs. 40000/-  in F.Y. 15-16.

Your Father can make investment u/s 80 C Rs.150000/- In F.Y. 16-17 to reduce tax 

If he is staying in rented accommodation he can deduct Rs 24000/- u/s 80GG for rental accommodation.

If your Mother has a PAN No; your Father can Invest some of the FDs in your mothers name and make her an Assessee. You please see that the income does not exceed Rs. 3 lack in each case.

But if Amount Gifted to your mother by your father cubbing provision will be applied

There are ways to avoid clubbing provisions whic cannot be discussed here.

Thanks for helping me. 

Dear Manian ji can you help to abiod clubbing proviosions?  If you dnt mind you can email me ysamit.das @ gmail.com