Here's probably my only entry for Category A: The Missing Set. I chose to do Mount Doom. I'm not really sure why LEGO never did this scene, seeing how it is the most important of the movie.
This comes three play features, all coinciding with the movie, as are the minifigure's outfits: Sam's dirty, and without all the equipment printed on his actual, LEGO-made torso, and Frodo's dirty and torn.
Setname: 79022 Mount Doom
Parts: 201
Minifigures: 3
Price: $24.99
The play features, like a handle for Frodo to hold onto.
A lever, that if you pull...
...this will happen.
And finally, a launcher that fires, well... fire. ;)