Explanation:

The correct answer is option A, which is "Both (i) and (ii) are correct and (ii) is the correct explanation of (i)". Let's understand the given statements and their explanations in detail.

(i) The first statement says that "India is a member of the International Atomic Energy Agency (IAEA) and one of the few countries that have developed nuclear power on its own." This statement is correct as India is indeed a member of the IAEA since 1957 and has developed nuclear power on its own, without any foreign assistance, through its three-stage nuclear power program.

(ii) The second statement says that "India has not signed the Nuclear Non-Proliferation Treaty (NPT) but has signed the Comprehensive Nuclear-Test-Ban Treaty (CTBT)." This statement is also correct as India is not a signatory to the NPT but has signed the CTBT in 1996, although it has not yet ratified it.

Explanation of (i) by (ii):

The second statement (ii) explains why India has not signed the NPT, which is a treaty aimed at preventing the spread of nuclear weapons and promoting disarmament. India has a long-standing position of advocating for nuclear disarmament and a world free of nuclear weapons, but it believes that the NPT is discriminatory as it recognizes only five countries (US, UK, Russia, China, and France) as nuclear-weapon states and denies the same status to others. India also objects to the fact that the NPT perpetuates the existing asymmetry in the global nuclear order, where some countries possess nuclear weapons while others do not. Therefore, India has refused to sign the NPT and has instead pursued an independent nuclear policy based on its national security interests.

Conclusion:

In conclusion, both statements (i) and (ii) are correct, and statement (ii) provides the correct explanation of why India has not signed the NPT. India's nuclear policy is based on its commitment to peaceful uses of nuclear energy, nuclear disarmament, and maintaining a credible nuclear deterrence.