Correct Response: D. Sheltered English immersion (SEI) emphasizes differentiating content instruction to provide English language learners with the scaffolds and language support they need to develop content knowledge and related academic language. A and C are incorrect because SEI is not focused on providing intensive remedial instruction or early identification of disabilities. B is incorrect because, while use of SEI may ultimately improve students' academic test scores, this is not the primary goal of the model. Also, there are differences between SEI and content-based language development as instructional models. For example, the former is taught by a content-area teacher who has received special training in SEI, while the latter is taught by an ESL teacher.