What T Adaptor would I need to get for a Nikon D3000?

I've been meaning to get one for a while but not sure whether I need the T adaptor 1.25" or the T adaptor 2" for my Nikon D3000 to go with the Nikon T ting. Any help would be appreciated.

That depends upon what you are attaching your camera to, not the camera

My telescope uses a 1.25 inch to Nikon T-mount adapter