Under the Secured Transactions Article of the Uniform Commercial Code, what is the order of priority for the following security interests in store equipment? I. Security interest perfected by filing on April 15. II. Security interest which attached on April 1 but for which there was no filing. III. Purchase money security interest which attached April 11 and perfected by filing on April 20.

A. II, I, III B. I, II, III C. III, I, II D. III, II, I