Spy that Rajeev is looking for

Who do u guys think is going to be the spy? In my opinion I think its going to be completely different person but I have my doubts on Ali. He seems like a very nice guy but always the nicest person on screen ends up being the worst one. It can also be completely different person and not from the 6 cadets. It can be one of the teachers or ladies like captain shalini and ritu.