What Does Net Capital Outflow Measure

What does net capital outflow measure?

A) foreign assets held by domestic residents minus domestic assets held by foreign residents
B) the imbalance between the amount of domestic assets bought by domestic residents and the amount of foreign assets bought by foreigners
C) the imbalance between the amount of foreign assets bought by domestic residents and the amount of domestic goods and services sold to foreigners
D) domestic assets held by foreigners minus foreign assets held by domestic residents