The Country of Aquolina Does Not Trade with Any Other

The country of Aquolina does not trade with any other country.Its GDP is $20 billion.Its government purchases $3 billion worth of goods and services each year,collects $3 billion in taxes,and provides $2 billion in transfer payments to households.Private saving in Aquolina is $4 billion.What is investment in Aquolina?

A) $4 billion
B) $3 billion
C) $2 billion
D) There is not enough information to answer the question.