Step 1: Understanding instructional aids.
Instructional aids are tools used to make teaching more effective.
They are classified as audio aids (hearing), visual aids (seeing), and audio-visual aids (hearing + seeing).
Step 2: Nature of given options.
- Puppet Show: Both visual (puppets) and audio (voice) → Audio-visual aid.
- Drama: Involves both speech and visual performance → Audio-visual aid.
- Public Address System: Provides only sound, no visual part → Purely audio aid.
- Cinema: Combines sound and visuals → Audio-visual aid.
Step 3: Elimination.
Since Public Address System is only an audio aid, it is not an audio-visual aid.
Step 4: Conclusion.
Therefore, the correct answer is Public Address System.