colors seen on tv results from color A) Subtraction B) Addition C) none of the above?

Answer 1

Addition. Look really close on an old-type tv and you'll see the three diffent colors, red, blue, green.

Answer 2

In CRT TV sets, Red Green and Blue phosphors are combined to produce the colors seen, this is addition.

but in some cases, like an LED screen or a one chip DLP projector, first subtraction (white light is filtered to make RED GREEN and BLUE) and then addition.

Some newer projection TV sets have a 6-color filter wheel, and the increase in color quality is quite noticeable.