The number 3047 is written in digital (seven-segment) style just above the water. Which panel shows its water image?

In water the order stays 3, 0, 4, 7 and each digit turns upside down. The 3 and 0 look the same; the 4 now has its short arm at the bottom and the 7 becomes an L-like shape: (a). (c) leaves the 4 unflipped, (b) reverses the order, (d) is a half-turn.