In linear programming, what does it mean when we say that proportionality exists between a product and a resource? A) If one unit of a product requires two units of a resource, then three units of the product mt require six units of the resource. B) If one unit of a product requires two units of a resource, then three units of the product mt require three units of the resource. C) If one unit of a product requires two units of a resource, then three units of the product mt require four units of the resource. D) If one unit of a product requires two units of a resource, then three units of the product mt require one unit of the resource.