Efilling required for person not coming under tax slab

Answer to Q1.: Its voluntary to file income tax return if your income is less than basic exemption.

Answer to Q2: If Bank deduct tds from FD interest then you have to file income tax return and claim refund equal to tds amount deducted by bank.

Answer to Q3: How you can come to know whether bank deduct tds or not, if your FD interest is more than Rs.10000/- then bank required to deduct tds u/s 194 A. However, you can avoid this tds by submitting Form 15G/H.

Hope from this there no more doubt in your mind.