Well..that depends on wht u want to perceive..and how sound are u in Acads/ Others. As it cant be generalized for everyone..I'm adding all the best options..I think u can find the best best one in them..
Option 1. Masters/ph.D
Good CGPA and GRE could definitely fetch an admission with full scholarship in a reputed foreign university since u are graduating from a Highest Ranked India University. Pursuing same in India, I feel would be waste of time/money.
Option 2. CAT/GMAT
If interested in doing an MBA, just take whatever job u get during campus placements and prepare well for CAT/GMAT, and surely u will get an advantage in the Interview Process as u come from a diversified background.
Depending on ur writing, communication and talking skills, u can choose between IIM or some foreign university.
Option 3. CIVILS - UPSC
There are not much of jobs in Govt. related to Biotechnology(None in IES) but u may choose for Group I - and choose the service u like.
But, this definitely needs much time/money.( 2/3 years and 1-3 Lakhs)
Option 4. Take IT Job
Enjoy ur IT job and put peace in life(may be 4-6 years) till u realize that u are something more having an IIT Degree and then start to choose between Options 1, 2, 3.
Option 5. StartUp
If u have a sound background in MBA related courses (which u need to take as Minor/ Free electives..at max of 6 courses combined), then u have enough knowledge on how to understand and manage a StartUp.