When was nuclear proliferation treaty extended indefinitely?

The correct answer is Option 3 - 1995

On 11 May 1995, the Nuclear proliferation Treaty was extended indefinitely. A total of 191 States have joined the Treaty, including the five nuclear-weapon States.

"India has consistently opposed international treaties aimed at non-proliferation due to their selective applicability to non-nuclear states, which perpetuated the dominance of the five established nuclear powers. As a result, India objected to the indefinite extension of the NPT (Non-Proliferation Treaty) in 1995 and refrained from signing the Comprehensive Test Ban Treaty (CTBT).