Final answer:
The availability heuristic most influences concept accessibility as it is based on recent or easily remembered information.
Step-by-step explanation:
The concept's accessibility is most influenced by the availability heuristic, which refers to the tendency to evaluate new information based on the most recent or most easily recalled examples. This cognitive bias suggests that if an example or instance is easily remembered, people may mistakenly believe it is more representative of the norm than it actually is. Accessibility can therefore be affected by recent events or information that has been vividly or repeatedly presented, making it readily retrievable from memory.