The correct answer is Option D: 8 countries.

The Shanghai Cooperation Organisation (SCO) is an international organization founded in 2001. It was established by the leaders of Russia, China, Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan. The main objective of the SCO is to promote regional security, economic cooperation, and cultural exchange among its member countries.

Here are the member countries of the Shanghai Cooperation Organisation:

1. China: China is one of the founding members of the SCO and plays a significant role in the organization. It is the largest economy among the member countries and has a strong influence in the region.

2. Russia: Russia is also a founding member of the SCO and is an important player in the organization. It is the largest country in terms of land area and has a significant influence in the Eurasian region.

3. Kazakhstan: Kazakhstan is a founding member of the SCO and is the largest landlocked country in the world. It plays a crucial role in promoting regional stability and economic cooperation.

4. Kyrgyzstan: Kyrgyzstan is a founding member of the SCO and is a small landlocked country in Central Asia. It has been actively involved in promoting regional security and economic development.

5. Tajikistan: Tajikistan is a founding member of the SCO and is a landlocked country in Central Asia. It has been actively participating in the organization's activities and has benefited from regional cooperation.

6. Uzbekistan: Uzbekistan is a founding member of the SCO and is a landlocked country in Central Asia. It has been actively involved in promoting regional security and economic development.

7. India: India became a full member of the SCO in 2017. It is the second-most populous country in the world and has a growing economy. India's membership in the SCO has strengthened its ties with the member countries and has provided new opportunities for regional cooperation.

8. Pakistan: Pakistan became a full member of the SCO in 2017. It is a strategically located country in South Asia and has been actively participating in the organization's activities. Pakistan's membership in the SCO has enhanced its regional connectivity and economic cooperation.

Overall, the Shanghai Cooperation Organisation consists of 8 member countries, including China, Russia, Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, India, and Pakistan. These countries work together to promote peace, stability, and cooperation in the Eurasian region.