Gross Domestic Product (GDP) per capita is a measure of the total output of a country that takes the gross domestic product (GDP) and divides it by the number of people in the country.

Option 1: China`s economy is the second-largest in the world, hence its GDP per capita is higher than India`s, making it not the correct answer.

Option 2: India, although a fast-growing economy, its large population significantly lower its GDP per capita, making it the correct answer in this case.

Option 3: Indonesia, with its relatively smaller population and stable economy, has a higher GDP per capita than India, hence it is not the correct choice.

Option 4: Sri Lanka although smaller in economy as compared to others has a comparatively higher GDP per capita due to its smaller population, hence it is also not the correct answer.

Hence, amongst the given options, India has the lowest GDP per capita.