A. Probably wouldn't climb, vines in my area tend to leave trees dead so I stay away, but if I did, I would be on the right trunk, platform towards the middle, feet or waist even with the split on the left trunk. Left handed shooter, but cover is better than worrying about a weak side shot.
B. Hanging off the center most fork of the top center v. My platform would probably be below the v, but not by much.
C. Only way I would hunt this is if I knew there was a big animal, and no other trees in area were alright, but I would be about 15' the trunk you have you stick on, and hoping the photographer was the target, set up for a drop shot.
D. All the way up, set up to shoot them as they stage before coming into the field. Platform probably just above upper thick branch on the left.
Disclaimer: Left handed and used to hunting thick public with a lot of pressure. We go high, thick, and deep to get a shot.
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