B.Sc Chemistry

Analytical chemistry, as this will help you to get in analytical research area in chemical, pharmaceutical, metallurgy, food processing, leather and other industries.

All three fields are good. But if you go for BCA, it will pay you more after completing Masters and there are lots of companies recruiting people from MCA. You can make your own start up.

You should try for Delhi University or Jamia Millia Islamia.

You can take up any specific course after B.Sc as there are lots of options. If interested to continue your studies in the same field, join for M.Sc course. A management oriented career line is also possible by opting MBA course. MCA is another feasible course option after B.Sc. For PG course admission, it is essential to clear entrance exams. LLB can also be opted after B.Sc provided you qualify CLAT exam. So, from the given set of course options, you can select the best one as per your interest area.

Don't leave your B.Sc right now. Do Masters in some other subject. You can also go for an MBA.