Which of the Following Statements About an Assignment Is True

Which of the following statements about an assignment is true?

A) For an assignment to be valid,the assignee must be aware of the nature and extent of any defenses that the party liable on the contract might have against the assignor.
B) For an assignment to be valid,the assignee must be put on notice of what rights she is getting from the assignment.
C) The assignee of a contract can obtain no greater rights than the assignor had at the time of the assignment.
D) An assignment only transfers benefits,not liabilities.