A navy three-piece suit creates the most closed upper colour area in this selection. Jacket, waistcoat and the visible trousers appear similarly dark blue. A pale shirt and dark tie sit in the central opening. The picture stops above the shoes, so it cannot show trouser hem length or the footwear combination. The back of the waistcoat is also hidden. Similar colour does not establish identical fibre composition across all the pieces.
Use this example to decide about the additional waistcoat area. Try a real waistcoat beneath the jacket and then on its own. Sit and check its transition to the trouser waistband without continually rearranging the pieces for comparison. Ask about the back construction if you plan to remove the jacket at the celebration. Add a full-length view with your intended shoes as well. This assesses the three-piece as a complete outfit rather than only through its quiet upper area. Choose the tie for your occasion and intended effect, rather than treating it as evidence of a particular fabric.