Bars A are rearranged to give bars B. Rearrange bars C by the same rule.

B lists the bars of A in reverse order, from right to left (A happens to be rising, so B is falling). Reversing C (medium, short, tall, medium-short) gives medium-short, tall, short, medium: (c). (a) sorts the bars from short to tall and (b) from tall to short, which is not the same as reversing C; (d) changes the colour.