Concept:Operation Black Board is a scheme introduced under the National Policy on Education (NPE) 1986 to improve basic facilities in primary schools.Explanation:The scheme was launched in 1987–88.It aims to provide minimum essential resources to all primary schools.These include at least one classroom per grade, two teachers, separate toilets for boys and girls, and proper teaching-learning materials.The focus is on increasing human and physical infrastructure at the primary level.Answer:Primary schools (Option A)