I would say C. Permable
Google def.(of a material or membrane) allowing liquids or gases to pass through it.
"a frog's skin is permeable to water
Porous- (of a rock or other material) having minute spaces or holes through which liquid or air may pass
Polar protic solvents actually speed up the rate of the unimolecular substitution reaction because the large dipole moment of the solvent helps to stabilize the transition state. The highly positive and highly negative parts interact with the substrate to lower the energy of the transition state.
I cannot fully remember but the charge of a compound always has to be the same. However, I believe that the sign of the Y2 means that it is positive 2.
so in my opinion it is in between b and c. use your best judgment.
Answer:
The answer is B. Limiting factors can lower birth rates, increase death rates.
