Concept:A lesson plan is a structured roadmap that helps a teacher deliver a lesson in an organized, goal-oriented, and efficient manner.Explanation:A lesson plan outlines what students need to learn and how it will be taught within a specific time. It helps the teacher sequence content logically, choose suitable teaching methods, and prepare appropriate activities and assessments. By planning ahead, the teacher can use time effectively, anticipate learning difficulties, and ensure the lesson is systematic and well-organized. This reduces confusion and makes teaching more effective and purposeful.Answer:Lesson Plan helps a language teacher in giving systematic and effective teaching (Option D).