Gross National Product (GNP) and Gross Domestic Product (GDP) are distinct yet linked economic indicators. Their sum is never zero. Primary Distinction: \[\text{GNP} = \text{GDP} + \text{Net Factor Income from Abroad (NFIA)}\]- A positive NFIA results in GNP exceeding GDP.- A negative NFIA leads to GNP being less than GDP.- Zero NFIA means GNP equals GDP.Therefore, option (D) is erroneous because the sum of GDP and GNP is contingent on NFIA, not necessarily zero.