Answer: C. The difference in cost over time between a loan at 10% and a loan at 8%.
Explanation:
The first bank cannot be held liable for damages relating to the loss of the opportunity to buy the carpets because they were not informed of it and so could not have made a decision based on it.
Another thing they cannot be held liable for is the merchant's inability to get another loan in time because it is assumed that there are other banks that the merchant could have gone to. What they can be held liable for however, is the difference in the types of loans.
The merchant had to get a loan with a higher interest rate because they couldn't honor their agreement so they will pay the difference in interest between their loan and the one the merchant was able to get.