Answer:
This is undercoverage bias because only those attending the concert will have an opportunity to register an opinion.
Explanation:
Undercoverage bias occurs when the sample chosen for a research is not representative of the entire population. Most times when research involving surveys to obtain the opinions of people on a subject matter, the entire population affected by the issue cannot be surveyed. A sample that represents the true population can be used for this research.
In the survey above, the sample that was surveyed was not representative of the entire population of citizens paying taxes on entertainment tickets. The selection process does not represent the true population.