In which year was India declared a polio-free nation?

Correct option is C

Sol. India was officially declared polio-free by the World Health Organization (WHO) in the year 2014, after no new cases were reported for three consecutive years. This was a major milestone in public health.
Explanation of each option: • (a) 2010 – By this time, India had made significant progress but was still reporting a few polio cases. • (b) 2011 – This was the last year India reported a case of polio, but official certification came later. • (c) 2014 – Correct. WHO declared India polio-free in 2014 after sustained surveillance and vaccination efforts. • (d) 2012 – India had no new cases in 2012, but WHO certification took place only in 2014 after a three-year disease-free period.