""Which of the following statements regarding the legal effect of Daniel's illness is LEAST accurate?
Paul was under a duty of immediate performance of his promise to deliver the cards on or before December 15 by reason of the express language of the contract and despite the illness of Daniel and the related developments.
Daniel's conduct after his illness constituted a waiver of the necessity of Paul's performing on or before December 15.
Daniel's illness and the related development excused Paul from his obligations to deliver the cards on or before December 15.
Prompt notice by Daniel to Paul of Daniel's recovery from illness was an implied condition of Paul's duty under the circumstances.