preferece order 

1 iit bombay mechanical

2 iit chennai cse 

3 iit chennai electrical

4 iit chennai mechanical

5 iit bombay civil

Hello Vamsi !

Computer science branch is more batter than the core branches in IIT ..as per based on the highest package given to the student always goes to CSE department..:)

So my preference would be

IIT C --->CSE

IIT B ---->MEchanical

IIT C ---> Mechanical

IIT C ---->Electrical

IIT B ----> Civil

(B for bombay and C for Civil )

Regards

Yagya