What are the LD50 and ED50 for a substance? What do they indicate?
A) Lethal dose for 50% of the population; Effective dose for 50% of the population
B) Lethal duration for 50% effectiveness; Effective duration for 50% lethality
C) Low dose for 50% effectiveness; High dose for 50% lethality
D) Lifetime dose for 50% of the population; Early dose for 50% effectiveness
