Identify the form of public sector enterprise in the following cases :
(a) It is under the control of concerned Minister of the Department.
(b) It enjoys maximum autonomy in all managemant activities.
( c) LIC and Air india are the examples of this form of enterprise.
(d) Minimum `51%` of the paid up captal is held by the government.
(e) This enterprise is most suitable when national security is concerned.
(f) These enterprises are set up under a special Act of parliament.