Use the Following to Answer Questions

Use the following to answer questions :
Scenario: Open Economy S = I
In an open economy GDP is $12 trillion this year. Consumption is $8 trillion, and government spending is $2 trillion. Taxes are $0.5 trillion. Exports are $1 trillion, and imports are $3 trillion.
-(Scenario: Open Economy S = I) Look at the scenario Open Economy S = I. How much is private saving?

A) $4 trillion
B) $2.5 trillion
C) $3.5 trillion
D) $1.5 trillion