From the passenger's (layman's) point of view, it could be "A, a round trip ticket", since the pax doesn't care about the airline's ticketing nomenclature and just wants to get from point A to B round trip regardless of airline.

From a ticketing or travel agent's point of view, it could be "D, a round trip ticket that uses two one way fares". If the agent booked it that way.

In the other thread you linked to in your message, you explain that it's definately not a circle trip ticket due to the fact that the outbound and inbound routes do indeed mirror each other.

I'm not familiar with what a point to point ticket is -- sounds like a generic term for any ticket since every ticket is point to point, no?

But, knowing you, tvl4free, being the expert that you are on finding ways to twist the ticketing rules to the frequent flyer's advantage, I'll bet on "E. a "bonanza for the frequent flyer" type RT tkt"

If it is, please tell us more!