Which of the following best describes a “school” under the relevant education act?

The most accurate description of a "school" under the relevant education act is that it refers to any elementary or secondary school. This definition encompasses a wide range of educational institutions that provide foundational education for children and adolescents, specifically targeting the age groups mandated by the act. Elementary schools focus on early education, while secondary schools prepare students for higher education or vocational careers.

In contrast, the other options do not adequately align with the general definition of a school within the context of the education act. For instance, structures used exclusively for administrative purposes do not fulfill the educational mandate of a school; similarly, institutions primarily focused on adult education and facilities for vocational training serve different educational objectives and are categorized separately under adult education or vocational training programs, rather than as traditional schools. Overall, defining a school as any elementary or secondary school aligns with the intent of the act to provide foundational educational services to the student population.