hello sir,i am persuing Bsc with biology & i want to do mba from iim.so, which feild should i choose(marketing,finance.....etc)?

In order to make a wiser decision regarding a specialization in MBA you first need to know what each of those are.

Its advisable that you log on http://www.youngbuzz.com/careers/careerprofile  and check the section on management which will tell you more about the streams, its career scope, remuneration, benefits, opportunities etc.

Nevertheless, the decision you take will depend on your interest. So
ideally get to know about the various streams first.

Hope this helps.