Abbott (an S Corporation), Bell, Costello, and Dilbertson form Best Partnership, an equally shared partnership. Each partner but Abbott has a December 31 tax year-end; Abbott's is June 30. The partners would like to choose a partnership tax year other than one ending December 31, but do not have a valid business purpose for doing so. Which of the following is an acceptable tax year-end they may choose for Best Partnership?
I. December 31
II. September 30
III. June 30
a. I and II only
b. I only
c. I, II, or III
d. I and III only