A Key Consideration in the Government's Decision in the Staples/Office

A key consideration in the government's decision in the Staples/Office Depot case was that

A) Staples charged lower prices in locations that were close to an Office Depot store.
B) Staples charged higher prices in locations that were close to an Office Depot store.
C) Staples and Office Depot had engaged in explicit price fixing.
D) Staples and Office Depot would be a natural monopoly if they were allowed to merge.