The Country of Hykania Does Not Trade with Any Other

The country of Hykania 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 Hyrkania is $4 billion. What is investment in Hyrkania?

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