In an Economy It Costs $1500 to Produce 2000 Units

In an economy it costs $1500 to produce 2000 units of output. If the costs increase to $2500, then the per-unit cost of production will have increased from:

A) $0.75 to $1.25.
B) $0.75 to $1.00.
C) $1.33 to $1.75.
D) $0.80 to $1.33.