Final answer:
The correct answer is less than 20 percent, as indicated by Mintzberg's research on the time allocation of managers.
Step-by-step explanation:
The correct answer according to Mintzberg is c) less than 20 percent, when, in fact, it is less than 20 percent.
Mintzberg conducted a study on the time allocation of managers and found that the majority of their tasks take less than 9 minutes to complete. His research indicated that only a small percentage of tasks took longer than this threshold.
Therefore, option d) is the most accurate representation of Mintzberg's findings, as it acknowledges that less than 20 percent of tasks take less than 9 minutes to complete.