In the Basic Keynesian Model,to Close a Recessionary Gap of $10

In the basic Keynesian model,to close a recessionary gap of $10 billion,government purchases must be

A) increased by $10 billion.
B) decreased by $10 billion.
C) increased by more than $10 billion.
D) increased by less than $10 billion.
E) decreased by less than $10 billion.