While finishing the unwinding , I dropped the handle , and Duke took off . He was quickly at the heels of another couple ( dogless , however ) who were out walking . " First day with the new leash , " Janet explained .

Pick from:
(I) None of the above choices .;
(II) Their dog had annoyed another couple .;
(III) Their dog had ran off with the lease .;
(IV) Their dog had gotten out of the leash .;
Q: What may have happened during this situation ?
(III)