Motorway_link makes the most sense to me because the road is essentially serves as a long on/off ramp for route 9. The only reason I would be hesitant is because I've never seen an example of a such a long motorway_link for a 2+1 road

note: CT DOT marked these roads as "minor arterial" but they connect to nowhere. Ends at a "collector" road in North Haven. Does not make sense as secondary considering the road network.

Ok, I'll send him a message