Answer:
B. The time spent on the task
Explanation:
The time that Dana spends carrying out her task is a cost to her. That cost can be calculated by ascertaining the gains or benefits she has missed due to the research.
If Dana were not doing the research, she would be engaged in other activities. Those activities could have been of benefit to her, be it financially or otherwise. The benefits foregone are the cost of Dana doing the research.
