The code 7bE2 mixes digits with a small and a capital letter. Which panel shows how it looks in the dashed mirror?

Reverse the order and flip every symbol: the 2 (first) looks like a 5, then a backward E, then the small b, which flipped looks like a d, and finally a 7 opening to the right: (c). (a) leaves the b unflipped, (d) is upside down and (b) is a half-turn (the b becomes a q-shape).