Remember opposites attract and same charges repel each other.
Object A= negatively charged.
Object A and B attract so B must be positively charged.
Object B and C repel so because B is positively charged C must also be positively charged.
Object C and D attract and because C is positively charged, D must be negatively charged.
How did you take a picture?
Answer:
dispersion
As per your query the splitting of white or visible light into its component colours is known as dispersion. The splitting of white light when it passes through a glass prism into its constituent spectrum of colours is hereby known as dispersion.