The correct option is B
1, 2 and 4 only
Explanation:
Statement 1 is correct: Members of SAARC are Afghanistan, Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan, and Sri Lanka.
Statement 2 is correct: Members of BIMSTEC are Bangladesh, Bhutan, India, Myanmar, Nepal, Sri Lanka, Thailand.
Statement 3 is incorrect: Members of SCO are China, India, Kazakhstan, Kyrgyzstan, Russia, Pakistan, Tajikistan and Uzbekistan.
Sri Lanka is one the six Dialogue Partners.
Statement 4 is correct: There are 54 members of the Commonwealth of Nations. India and Sri Lanka both are members of the Commonwealth of Nations.