Which stream of engineering should I choose?

In order to become an IAS officer, I won't suggest to go for Engineering as it would not give you much opportunities of IAS Courses and preparation. You can opt for BA specialization program which provides knowledge of economics, public finance, research methods, public policy, leadership, strateg

I basically agree with the contention that B.Tech is not that suited for UPSC. But, the fact is that there are more number of B.Tech graduates succeeding in IAS. I don't know what subjects they choose.

Go for Electronics or IT.

To be an IAS officer, it doesn't matter which stream of engineering you choose as there are wide range of subjects to choose from. You should focus on your area of strength and interest and writing skills. You will be able to get through.