its the circulatory system
The right answer is smelly garbage.
Infestation is the penetration into the body of a parasite whose nature is not microbial.
smelly garbage is not synonymous of infestation, because the olfactory system only detected smelly metabolites of these microorganisms. This does not necessarily mean that the microorganism has managed to penetrate the body.
By cons other proposals are signs and tools for infestation (torn packaging with food leaking out, dead insect bodysuits, feathers, and fur).
C The rods will attract each other because they are both positively charged.
I believe that the answer to this question is, that laws can be made to prevent certain things/ amounts of things to be used up.