Answer:
b. knowledgeable user.
Explanation:
In the scenario stated in the question, the best line of defense by Temp-Set is than Stan is already a knowledgeable user who is aware of the dangers of the thermostats and thus there is no need for warning.Temp-Set’s best defense is most likely knowledgeable user. When a particular danger is commonly known by the user of a product, there is no need for the manufacturer to warn the user of such product. For example, McDonald chicken contain high cholesterol, this is a common knowledge and as such there will not be the need to warn the consumers.