The bond for 1 year(varies in different colleges in the state)  is for all students studying MBBS in Maharashtra state government college whether coming from any MBBS exam. It can be done in any government college and hospital, Phc, Rh or district hospital. 

The students who opted the bond they signed to serve in rural hospitals for a year or more after completion of the MBBS course.

Incase you are not interested to do the service (as per the bond) in some colleges though it is must and in others you can buy out as in you can pay bond money to skip rural service. It can be any amount as per college policy.

I hope you get the meaning.

All the best!