(a) An employee of a participating subdivision is included within the coverage of the optional group term life program on that day in the first month in which:
(1) the employing subdivision is participating in the program for coverage of all members it employs;
(2) the employee is a member of the retirement system; and
(3) the employee is required to make a contribution to the retirement system.
(b) Once established, coverage of a person in the program continues until the last day of a month in which a requirement of Subsection (a) is not met.
(c) The optional group term life program constitutes "group term life insurance purchased for employees" as described by Section 79, Internal Revenue Code of 1986.