Obviously. But the countries that did ratify it (all of them) are legally bound not to recognise a nation that does claim a body in violation of the treaty. So while I could form the "People's Liberation Front of the Moon" tomorrow and start claiming great big chunks of it - nobody would actually care or acknowledge it in any way. The main function that countries have is sovereignty over their citizens, which only comes about when they are recognised by other counties who then stop claiming sovereignty over the same citizens.
A. Yes, you are technically correct.
B. It's a pointless clarification.
C. It does not have any impact at all on the wider point, of who can claim bodies.
D. You are an idiot.