How do I register a game idea as mine legally before turning it in?

[tolu619]

Ok.Please can anyone explain this rule?Its one of the terms of the competition.
"13. I warrant that I am the sole owner and author of said material, that I have registered said material with the Library of Congress, Writers Guild or equivalent, that I have the exclusive right and authority to submit the same to them upon the terms and conditions stated herein. I will indemnify them and their clients of and from any and all claims, loss or liability (including reasonable attorneys' fees) that may be asserted against them or any of their clients, or incurred by them or any of their clients, at any time in connection with said material or any use thereof."