Answer:
B) Ace Builders' cost of capital.
Explanation:
Boone Brothers currently operates in a business that is related to Ace Builders's business but it is not the same to be involved in part of a industry than being involved in the whole industry.
Therefore Boone Brothers should use any information they can get from Ace to try to evaluate their own expansion project. Not only can Ace's cost of capital be useful, several other information like total construction periods, resources needed for permits and authorizations, etc.