I'm doing my btech 4rth year in electronics and instrumentation engineering.I need to choose a subject as elective and the subjects are computer networks, digital control systems.im unable to choose one among them... please help me.. I need to submit my choice to my faculty.kindly help me as soon as possible.

Chose which every you have most interest in, it's pointless studying a subject that doesn't interest you at all, as you will only fail.