Place this clip after you show the question and before you show the solution, then follow the reveal with the Bell Ding Sound Effect for a correct answer or a Dun Dun Dun cue when the result surprises the class.
حول هذا الصوت
This thirty second clip is built for the prepare the answer moment, linked in its upload note to entering a question in Vietnamese. It creates a tense, focused feeling, like the pause while someone thinks, checks their work, and gets ready to respond before the answer is revealed to everyone watching.