In the Keynesian-cross model, if the MPC equals 0.75, then a $2 billion increase in government spending increases planned expenditures by ______ and increases the equilibrium level of income by ______.
选项：

A:$2 billion; $4 billion
B:$0.75 billion; $1 billion
C:$0.75 billion; $0.75 billion
D:$1 billion; $4 billion