How do you remember other people so that you can recognize them easily?
Normal people's answer would be to look at their face closely.
Because everyone's face would be different and had distinct features that would allow them to recognize each other. Not to mention, humans were already trained to recognize humans' face ever since they were babies naturally.
But if this question was asked to Nan Hua, her answer would be their body proportion along with their face.
Because even with the advancement of technology, completely changing one's body structure would be very difficult. They could add more layer of clothes and then some other additional that would hide them, but if they have to become skinner or smaller, then it would be difficult.
Illusion device or something like that could be used, but people with high mental strength would not be fooled.
