How many persons, among the Central Vigilance Commissioner and Vigilance Commissioners, can belong to a specific category according to Section 3 of the Central Vigilance Commission Act, 2003?

Section 3. Constitution of Central Vigilance Commission: (3) The Central Vigilance Commissioner and the Vigilance Commissioners shall be appointed from amongst persons-- (a) who have been or are in an All-India Service or in any civil service of the Union or in a civil post under the Union having knowledge and experience in the matters relating to vigilance, policy making and administration including police administration; or (b) who have held office or are holding office in a corporation established by or under any Central Act or a Government company owned or controlled by the Central Government and persons who have expertise and experience in finance including insurance and banking, law, vigilance and investigations: Provided that, from amongst the Central Vigilance Commissioner and the Vigilance Commissioners, not more than two persons shall belong to the category of persons referred to either in clause (a) or clause (b).