Seven pieces of table lamps with different shades A, B, C, D, X, Y & Z - are to be arranged along one wall of a show room for display. Each lamp must be placed along the wall at one of seven electrical outlets, numbered one through seven consecutively, according to the following conditions. A must be package an outlet adjacent to the outlet at which X is placed. B must be placed at an outlet that is adjacent to an outlet at which either D or Y is placed. Z cannot be placed at an outlet adjacent to the outlet at which C is placed. C must be placed at outlet number two. If A is placed at outlet seven, which of the following must be true?