Venting Tank Water Heater - vent through roof options.

[schafphoto]

I am moving an old WH across a laundry room to accommodate a laundry sink. The old 1930 location has a single-wall, straight, sheetmetal vent through a pie tin escutcheon on the ceiling and then through the roof to a capped vent. I'd like to avoid cutting another hole in the roof (unless it's in the eave). Someday the house may get a tankless in the new location, but not this time.
The pathways to vent A, B, C on the drawing all are doable but I don't think it's good form to have a sloping vent above a doorway where people can touch it so I doubt B will work. (8'5" lath and plaster ceiling)
Your thoughts on my options and how I would go through the outside wall if path A were an option.

Thanks

 

[Twowaxhack]

I’ve done it both ways. Use type B vent, most likely.

Drill through the wall with appropriate holesaw. Follow the directions of the heater for venting and the manufacturer of the vent pipe.,

Good luck to you