Final answer:
In the case of a negative externality, the cost to producers will be less than the cost to society, because societal costs such as environmental and health impacts are not accounted for by the producers. (option c)
Step-by-step explanation:
When a negative externality exists in a market, for instance, pollution from a factory, the social costs of that externality are not fully borne by the producer or the consumer of the product causing the externality. Instead, they are incurred by the wider society who are not part of the exchange - for example, through the impacts of pollution on health and the environment. Therefore, the cost to producers will be less than the cost to society since the producers do not face the full social costs of their actions. This discrepancy can lead to what is known as market failure, where the market output is not efficient because not all costs and benefits are reflected in the market prices.
The correct answer to the question is: c. will be less than the cost to society.