B.Sc

You should go for biotechnology as it has good career opportunities.

sorry dear it is a very poor percentage to get a seat in Delhi University because here admission are on the basis of percentage and lot of application with very high percentage is already there . However you can try distance mode of DU and do regular course from other institution.
All the Best for your bright future.

Yes why not. If your degree is valid and you fullfil the eligibility criteria of that government institution than you will get an admission. You may to work hard to clear entrance test or get high percentage as there are very limited seats in the government colleges.

You can opt for MBA in IT if you are keen in going for IT infrastructure or Management. And there are other options also for MBA in IT like recruitment, IT planning etc. MBA in e-commerce you can choose if you look for option in developing website platform for e-commerce and software designing in these platforms. There is only one option available in e-commerce which is good for your career. Otherwise MBA in IT have more options.

Still B.Tech is the best for get maximum salary. Yes there are many rush in engineering but if you are good in your subject than you can get very good salary.

I think it is difficult to get admission in BSc. with this percentage of marks. Many colleges asked to 50 percent marks in your 12th. You should think about it either go for it or choose some easy subject to get good percentage in your graduation.

I think it's No, you can't do that because to get admission in bsc (it ) you have science with mathematics in your class 12th. However you can do MBA in it after your graduation.