Nike Will Build a Factory at Millville or Greenfield, but Not

Multiple Choice

Nike will build a factory at Millville or Greenfield, but not both.Alternatively, Nike may choose to build at neither location.The appropriate linear constraint to express this restriction using binary variables Y₁ and Y₂ is:

A) Y₁ - Y₂ $\le$ 1
B) Y₁ + Y₂ $\le$ 1
C) Y₁ + Y₂ = 1
D) Y₁ - Y₂ $\le$ 0