3. Article 30C of the 1977 Order and these Regulations, as well as not applying to a dwelling-house mentioned in sub-paragraph (a) or (b) of paragraph (12) of that Article, shall not apply to—
(a)a dwelling-house which is wholly owned by a housing association which is not registered in the register maintained under Part II of the Housing (Northern Ireland) Order 1992;
(b)a dwelling-house which is used for providing living accommodation for a person who—
(i)is an employee of the Northern Ireland Housing Executive or of a housing association;
(ii)resides in the hereditament in connection with his employment by that body; and
(iii)has no liability for rates in respect of the dwelling-house during his period of residence there; and
(c)a dwelling-house which is wholly owned by a Northern Ireland department, a Minister of the Crown, an officer or body exercising functions on behalf of the Crown or a body established by or under a statutory provision.