Professional writing sample?

I have a Project Coordinator application question.

I am applying for a PC position in Clinical Quality. This company is asking for a professional writing sample. I don't have one. It's not like I have access to e-mails or standard operating procedures that I sort of wrote. I am thinking of submitting a short essay I wrote for grad school. One website said that I shouldn't submit something older that one year old, though, and that same website says that if I don't have one, I should make one up. How exactly do I do that?

Has anyone encountered this before, and if so, what did you submit?

usa jobs
usa jobs resume
usa hotel jobs
usajobs
usa jobs federal government
usa job in ksa
usa jobs
usa jobs login
usa jobs gov
usajobs.gov
www.usajobs.gov
usajobs.com
usajobs
usajobs.gov official