This question is ambiguous due to the broad term "audio-visual aids." While the answer key indicates (A) Slide Presentations and (C) Radio Programmes as correct, the other options could also be considered audio-visual depending on their implementation. For instance, group discussions (B) could incorporate audio-visual elements, and pamphlets (D) might contain images. The question would be clearer if it specified "electronically mediated audio-visual aids" or similar, to narrow the scope and avoid potential confusion.