(1) are part of the group on the basis of current or former employment or belong to(a) a professional order,
(b) a professional association whose membership consists of members of one or more professional orders,
(c) an association whose membership consists of persons engaged in the same trade or occupation, or
(d) a union or association of employees
that offers coverage under a group insurance contract or employee benefit plan or under an individual insurance contract concluded on the basis of one or more of the distinctive characteristics of group insurance to, makes such coverage available to or facilitates such coverage for its active members or retirees, either directly or through a legal person; and