Q.Which of the following correctly defines Gross Domestic Product (GDP)?

GDP is defined by where production happens (domestic territory), not who owns the factors producing it — that distinction is what separates it from GNP.

Option (a) describes GNP, not GDP — GNP is defined by residency of the producer, not location of production. Option (b) is exactly the textbook definition of GDP: the money value of all final goods and services produced within the domestic territory of a country during a year, whether the producing factors are owned by residents or non-residents. Option (c) describes NDP (GDP minus depreciation), not GDP itself — GDP is a gross concept, so depreciation is not deducted. Option (d) is backwards: $GNP = GDP + NFIA$, so $GDP = GNP - NFIA$, not "National Income minus NFIA" — and National Income (NNP at factor cost) is a different, further-adjusted aggregate altogether.

Confusing GDP (location-based) with GNP (residency-based) is the single most common slip; another is assuming GDP already deducts depreciation, which only "net" aggregates do.