Answer:
improvements to the building,
Step-by-step explanation:
Opportunity cost is the foregone advantage of not setting certain options in decision making. When a particular option is preferred over others, then benefit from the other options not selected are forfeited. The forfeited benefits represent the opportunity cost.
The value of opportunity cost is equated to the value of the next best alternative. Where there were more than two alternatives available, the next best alternative from the chosen option becomes the opportunity cost. In this case, improvement to the building was voted the second preferred option; hence it becomes the opportunity cost.