Simon has signed a contract with Miley agreeing to provide her company with $1,000$ frozen pizzas each week. The contract states: "This agreement can only be modified by a written instrument signed by the party to be charged with such amendment." But when Simon and Miley run into each other on the train, they agree that he will provide $750$ pizzas instead. Which of the following statements is true?

Answer

a$.$ As long as they both agree, they can amend the contract orally. They do not have to sign anything.

b$.$ For the change to be valid, both parties must sign an amendment because both parties are affected by it$.$

c$.$ Only Miley has to sign the amendment because she is the one to be charged by it$.$

d$.$ Only Simon must sign the amendment because he is the one to be charged by it$.$