A. on
B. to
C. with
D. in
🧠 Explanation:
The sentence “He delights in playing with children” uses “in” correctly. Knowing this helps students improve English grammar, ensuring clear sentences. The preposition “in” shows enjoyment in an activity. This is useful for writing essays or exams, enhancing clarity. Understanding prepositions is key for English classes, helping students communicate effectively. It aids in crafting sentences for reports or conversations, ensuring ideas are expressed accurately in academic projects, professional tasks, or daily communication scenarios where proper grammar improves understanding and professionalism in language use.