Hiram Brody Worked as a Research Assistant for Rheem Shareef,who

Hiram Brody worked as a research assistant for Rheem Shareef,who was one of his professors.Rheem regularly asked Hiram to proofread documents that she had written.Hiram therefore was not especially excited when he was asked to proofread a research proposal that Rheem had drafted in connection with a major project for which she had recently received generous funding from the government .He did,however,become very excited when he read paragraph 14 of the document: "I will offer Hiram Brody the position of joint-investigator.That position will require him to both resign from his present post as my research assistant and take a leave of absence from his current studies.Given the nature of the project and given his outstanding qualifications,Hiram will be paid $8000 per month for a period of eighteen months." After Hiram hurriedly finished proofreading the document,he unsuccessfully tried to contact Rheem to talk about his new position.He learned,however,that she had left town,on very short notice,to be with a sick relative who lived outside of Canada.He then wrote a letter to the Chair of his University Department in which he both resigned as Rheem's research assistant and took a two-year leave of absence from school.He also left a message on Rheem's telephone answering machine in which he said,"I accept.I can't wait to begin working as your joint investigator." Hiram consequently was very angry when Rheem said,after she had returned from abroad,that she had changed her mind and had hired another person to serve as her joint investigator.Hiram insists that she cannot do so because he had already accepted her offer.A court,however,would say that Hiram could not create a contract by leaving a telephone message for Rheem because

A) she had communicated her offer to him in writing.
B) she had given the document to Hiram as a proofreading assignment,rather than as a contractual offer.
C) it is impossible to accept an offer while the offeror is outside of the country.
D) he was already contractually required to work for her as a research assistant.
E) the document contained an invitation to treat,rather than an offer.