Persons presumed wholly dependent

(1) For the purposes of articles 40 to 47 of this title, the following described persons shall be presumed to be wholly dependent (however, such presumption may be rebutted by competent evidence): (a) Widow or widower, unless it is shown that she or he was voluntarily separated and living apart from the spouse at the time of the injury or death or was not dependent in whole or in part on the deceased for support; (a.5) A person who is designated in a designated beneficiary agreement for purposes of receiving workers' compensation benefits in accordance with the provisions of article 22 of title 15, C.R.S., unless it is shown that the designated beneficiary was voluntarily separated and living apart from the other designated beneficiary at the time of the injury or death or was not dependent in whole or in part on the deceased for support; (b) Minor children of the deceased under the age of eighteen years, including posthumous or legally adopted children; (c) Minor children of the deceased who are eighteen years or over and under the age of twenty-one years if it is shown that: (I) At the time of the decedent's death they were actually dependent upon the deceased for support; and (II) Either at the time of the decedent's death or at the time they attained the age of eighteen years they were engaged in courses of study as full-time students at any accredited school. The period of presumed dependency of such persons shall continue until they attain the age of twenty-one years or until they cease to be engaged in courses of study as full-time students at an accredited school, whichever occurs first.