James cultivates fruit trees in his garden, and these attract butterflies and bees. Which of these is not an externality in this situation?
- ANeighbours may be stung by the bees that pollinate the trees.
- BNeighbours may buy fruit more cheaply from James than from the local supermarket.
- CNeighbours may enjoy better air quality as the trees naturally improve the atmosphere.
- DNeighbours may like to watch the activity of the wildlife at no cost.