This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
Education charts that are serially flashed audience as the talk is being given is known as 
Select and explain. 
A. Flip charts, B. Pie charts, C. Controlled charts, D. All of the above
A: Flip charts
Answer: A: Flip charts 
Explanation: None