Option a is the correct answer. The term "Agraharika" and its associated practices were not part of the Mauryan administrative structure. "Agraharika" refers to Brahmins who received villages as state land grants in the 5th-6th centuries. These villages, known as Agrahaara, were exempt from revenue and held certain privileges. The Mauryan administration had officials like Yukta, Pradeshika, and Rajjuka.