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.
At one later moment, its speed is 1. 20Mm/s (non relativistic because v is much less than the speed of light).
A is false because light and sound waves can both reflect off of objects
