Since Non-Market Exchanges Are Excluded from Measures of GDP, the GDP

Since non-market exchanges are excluded from measures of GDP, the GDP measure tends to

A) underestimate the total production of an economy.
B) overestimate the total production of an economy.
C) be of little significance in determining the total production of an economy.
D) be of little use to anyone but market economists.
E) place too much value on market transactions.