Figure A is related to figure B in a certain way. Which figure is related to C in the same way?

Nothing moves from A to B; only the colours swap — every orange part becomes white and every white part orange (the dot stays put). Swapping the colours of C's six triangles gives orange exactly where C is white: (a). (b) shades the right number of parts in the wrong places, (c) misses one part, and (d) simply turns C round.