Indian Institute of Foreign Trade 2011 Solved Paper

We are given that
Prof. Chakravarty and Prof. Equbal have to be selected.
Also, Prof. Das is selected.
2 of the members are students thus, Prof. Ahuja an Prof. Banerjee cannot be selected.
Prof. Ahuja and Sushil have to be together. Thus, Sushil cannot be selected.
Prof. Das and Queen cannot go together. Thus, Queen cannot be selected.
Thus, Prakash and Ravi will have to be selected.
But, Prakash cannot be put with Ravi.
Thus, no team is possible.
Hence, option D is the correct answer.z