In which of the following situations would the contract not be discharged by agreement? Select one: O a. A condition subsequent that calls for termination of the contract has not been met. O b. The two parties have reached a verbal agreement with regard to terminating the contract. O c. Both parties agree to call off the contract under which one paid the other $5000 for work that has not yet been performed, but the other now promises to return the $5000. O d. Both parties agree to let a new person be substituted into the contract in place of one of the old parties. O e. Both parties to the contract agree to call it off before either one has performed