To be honest most, if not all, of them look like males.
A and B are males as the females of this colour are silver.
C is a male because he is very colourful and the females of this colour either don't have stripes and are plain silver or they have just a hint of stripes.
D might possibly be a female as this one is much paler compared to C, and some females do have very pale stripes. But D also has long pointy fins which suggests a male.