Which decorating technique is suitable for all four letter styles?

The correct choice is pen and ink drawings, as this technique is versatile and can be effectively applied to all four letter styles commonly used in calligraphy. Pen and ink work allows for a variety of line thicknesses, shading, and intricate detailing, making it suitable for both formal and informal lettering styles. The fluidity of ink enables calligraphers to explore different artistic expressions and enhance the appearance of each letter, regardless of its style.

Watercolor washes, while beautiful, tend to be more suited for certain styles that embrace softer transitions and color gradients, potentially clashing with more structured letter styles. Pencil sketches are primarily used for preliminary drafts and may not provide the refinement needed for final calligraphic works across all styles. Block printing has a distinct aesthetic and is inherently different from traditional calligraphy, limiting its applicability to only certain formats of lettering. Thus, pen and ink drawings stand out as the technique that seamlessly integrates with the diverse approaches present in calligraphy.