A is for Alpha Quadrant. The north-west quadrant of the galaxy in 2-D maps of the Milky Way galaxy in the fictional Star Trek universe.
B is for Berengaria VII. There be dragons there.
C is for Ceti Alpha V. There was no need to go down to the planet. Dr Marcus should have just fired the Genesis Device at it and saved everyone alot of trouble.
D is for Denobulans. Generally mild-mannered and affable, but they had their moments.