Which of the following refers to text features that aid instruction?

The term that best refers to text features that aid instruction is instructional devices. Instructional devices are tools or features within a text that support learning and comprehension. These can include charts, graphs, headings, bullet points, and other visuals that help convey information more effectively and facilitate understanding of the content.

Transitional phrases, while important in guiding readers through the flow of a text, do not encompass the broader range of features that support instruction. Grammar structures pertain to the rules of language rather than features specifically designed to enhance instructional clarity. Textual coherence refers to how ideas connect within a text; it is an important characteristic for understanding but does not directly describe specific features used to aid instruction. Thus, instructional devices encompass the tools and features explicitly designed to enhance the learning experience, making it the correct answer.