CEo's, managers, and entrepreneurs measure an industry structure before entering that industry to compete based on market forces. If a food truck chooses to participate in a gathering of food trucks based on a tweet of where and who will be there and their core strength to compete is that they are unique in their food product they offer, this is an example of a weak _________ to their product. "

a) rivalry

b) threat of new entrants

c) threat of substitutions

d) bargaining power of customers