Shingles to Tar and Gravel

I'm in the middle of a home addition. The existing roof is tar and gravel and the addition is a gable. I need to know the proper way to tie in the new roof where it meets the tar and gravel. Any suggestions would be greatly appreciated.

Thanks for the info

I kind of assumed that the T&G was on a flat roof, not gabled. Making C the proper choice, though I've seen more than a couple "roofers" that would go ahead and shingle the flat.

In this case, if reroofing the T&G isn't an option and there's not a qualified hot contractor in the area, I'd spud back 12" of gravel, heat fuse an APP modified bitumen to the spud zone, leaving about 3" of head space between the membrane and gravel line, extend the modified up the slope about 2 vertical feet (probably takes 2 roll widths), shingle over the top of the modified, and pour an asphalt or coal tar coating (depends on what kind of "tar" your roof is made of) over the tie-off area, then spread gravel back into the coating. Should last until you're in need of a new flat roof.