(A) World Bank
The World Bank prepares the World Development Report. (UNDP publishes the Human Development Report.)
Source: Development, Chapter 1 (Sources for Information section)
The passage under "Sources for Information" explicitly states that data is taken from the World Bank (World Development Indicators). The World Development Report is a well-known annual publication of the World Bank. A common exam trap is confusing it with UNDP's Human Development Report — do not mix the two up.