Definition: A histogram visualises the distribution of data over a continuous interval or certain time period. Each bar in a histogram represents the tabulated frequency at each interval.
According to the given histogram,
0-20 years occur 15 times,
21-40 years occur 40 times,
41-60 years occur 40 times,
61-80 years occur 15 times.
This shows that the data is symmetrical and the majority of the attendees were between the ages of 21 and 60 (40 times).
Answer: correct choice is B.
