A local school system shall enroll in prekindergarten all 4-year-old applicants who are from families with economically disadvantaged backgrounds or who are homeless. For vacancies remaining after compliance with §A of this regulation a local school system may enroll 4-year-old applicants who are not from families with economically disadvantaged backgrounds but who represent a student population that exhibits a lack of school readiness. Prekindergarten Programs for 3-Year-Old Children. A local school system or qualified vendor may establish a prekindergarten program enrolling 3-year-old applicants who are from economically disadvantaged or homeless families, or who represent a student population that exhibits a lack of school readiness. A local school system shall be in compliance with 34 CFR §300.115(a)(b) and COMAR 13A.05.01.10 regarding children with disabilities. A prekindergarten program for 3-year-old children shall meet the requirements of Regulation .05 of this chapter.