Correct Answer:
B. ECO
The correct answer is ECO. The Regional Cooperation for Development (RCD) was an organization established in 1964 by Iran, Pakistan, and Turkey to promote economic and cultural cooperation. In 1985, the RCD was restructured and renamed the Economic Cooperation Organization (ECO), expanding its scope and membership. SAARC (South Asian Association for Regional Cooperation) and SCO (Shanghai Cooperation Organization) are distinct regional organizations with different origins, member states, and objectives. Therefore, options A, C, and D are incorrect.