MacBeth Homes has agreed to build the Adams family a new home for $300,000 on a lot beside a river. Which event might amount to frustration of this contract?

a. There is an increase in the price of lumber such that MacBeth Homes will no longer make a profit on the contract.b. A MacBeth Homes employee strike causes delays to the construction project by a few weeks.c. The land on which the home is to be built is washed away in a flash flood.d. MacBeth Homes is unable to buy the slate shingles specified in the contract because they are no longer being manufactured.