Step 1: Understanding the Question:
The question relates to the garment construction process, specifically how to arrange paper pattern pieces on fabric that has a distinct "nap" or "direction."
Step 2: Detailed Explanation:
• Most fabrics have a "two-way" layout, meaning patterns can be placed up or down.
• However, unidirectional (one-way) layout is mandatory for fabrics with a "nap" (like velvet), a directional print, or a distinct "lustre/sheen" that changes when turned upside down.
• Satin (A) is a weave with long floats that reflect light in a specific direction. If you place one part of a sleeve "up" and another "down" on satin, the two pieces will look like slightly different colors when the garment is worn because of light reflection.
• Sheers (B), Ginghams (C), and standard Rayons (D) usually do not have this directional light-reflecting property unless they have a specific directional print.
Step 3: Final Answer:
Satin requires a unidirectional layout.