Which of the following is primarily used for text in graphic design to create impactful visuals?

Text layers are essential in graphic design for creating impactful visuals because they allow designers to manipulate text in versatile ways. By using text layers, designers can adjust font styles, sizes, colors, and placements independently from other graphic elements in a composition. This flexibility enables the creation of hierarchy and emphasis in the design, drawing the viewer's attention to specific messages or information.

Text layers also facilitate the application of effects such as shadows, outlines, and gradients, enhancing visual appeal and ensuring the text integrates well with other design elements. They support layering and can be edited or animated easily in many graphic design software, allowing for greater creative freedom. This makes them an indispensable tool in conveying messages effectively and creatively in various types of media, including digital and print designs.

In contrast, other choices such as shape tools, raster images, and patterns serve different purposes. Shape tools are more focused on creating geometric designs, raster images refer to bitmap graphics which do not allow for easy text manipulation, and patterns are used for decorative backgrounds rather than for text emphasis.