According to grammar rules and most style books, you would hyphenate all compound numbers from twenty-one to ninety-nine. Therefore the correct answer is b, ninety-eight.
Contract in colours: black and white = lack of movement, frozen. Coloured = free flowing movement in the blend of colours.
It's often futile to try to convince people that they should adopt a particular political position, but if you try, make sure to appeal to logic. Try to eliminate as much emotion from your argument as possible.
