Answer:
B) NSB wins because the modification has to be in writing.
Explanation:
If the contract specifically states that any modifications or addendums must be done in writing and must be signed by the companies' presidents, then any verbal agreement that modifies the contract is not enforceable. So the original contract is still in place and since Mid-American didn't perform, NSB can sue them and will win.
Contracts this large must be done in writing and signed under UCC rules, regardless of any specific clause.