Concept:Authentic materials are those created for real-world communication, not for classroom use.
Explanation:Authentic materials come from real-life contexts like newspapers, menus, or advertisements.
They expose students to language and content as used outside the classroom.
Materials written by a teacher for her class are designed for teaching, not real life.
Materials from authorities may be useful but lack real-world origin unless based on actual content.
Items children bring from home are personal but not automatically authentic.
Thus, only materials written or developed in real-life content fit the definition.
Answer:C. materials written or developed in real life content.