We have already stated that the respondents have contended that the question of constitutional validity of granting exemption to buildings belonging to charities, religious or secular from rent control legislation as offending the equal protection clause of article 14 has been concluded by the observations made by this Court in P J. Irani 's case (supra) while Counsel for the petitioners and the appellants on the other hand have urged that it is not; according to Counsel for the petitioners and the appellants all that the observations made by this Court in that case decide is that the classification of buildings belonging to Hindu, Christian and Muslim religious public trusts as also to public charitable trusts could be regarded as a reasonable classification based on intelligible differentia but that test of nexus which is also required to be satisfied for purposes of article 14 has not been pronounced upon by this Court and this aspect is still open to argument We shall proceed on the basis that the question is res integra and consider whether the respondents, particularly the State Government have furnished proper material on the basis of which the exemption granted can be justified.