Sec 40(a)(iib)

Following expenditure shall not be allowed as deduction for the purposes of computation of
income of State govt undertakings under the head 'Profits and gains of business or profession'
in respect of :
(A) royalty, license fee, service fee, privilege fee, service charge or any other name whatever called if such royalty etc., is exclusively levied on a State Government undertaking by the State Government; or
(B) any amount which is appropriated directly or indirectly from a State Government undertaking by the State Government.

Can anyone explain me why it is not allowed?? Any reason behind that??