We are given that, Prof. Ahuja and Sushil have to be together and Prof. Chakravarty and Prof. Equbal have to be selected Thus, 4 of the committee members are Prof. Ahuja, Sushil, Prof. Chakravarty and Prof. Equbal. We see that Prof. Equbal has to be selected and is present in all the options A,B,C. Hence, the correct answer is None of the above.