Which type of production may raise GDP but reduce social welfare?

Correct answer: Production of harmful addictive substances

GDP counts the market value of final goods and services, so legally recorded production of addictive or harmful substances can increase measured GDP. However, their consumption may cause illness, dependence, family harm, crime, and other social costs that GDP does not subtract fully. Therefore option A is correct. School construction, clean energy, and vaccination generally create productive or health benefits, although their exact welfare effects can still depend on context.