This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Health education & planning, Subject name: Social & Preventive Medicine
[{'content': 'Audio video visual guides include \nSelect and explain. \nA. Radio, B. Television, C. Slides, D. Films', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Audio-visual aidsNo health education can be effective without audiovisual aidsAuditory aids:Radio, tape-recorder, microphones, amplifiers, earphonesVisual aids:Not requiring projection: Chalkboard, leaflets, posters, chas, flannelgraph, exhibits, models, specimens etcRequiring projection: Slides, film stripsCombined A-V aids:Television; sound films, Slide tape combinationRef: Park; 23rd ed; Pg 863', 'role': 'assistant'}]