The right answer is <span>A) semi-permeable membrane
<span>A semi-permeable membrane is a membrane permeable to a liquid (solvent) and impermeable (or poorly permeable) to substances dissolved in the liquid (solute).
</span>The tubule of a kidney consists of a semi-permeable membrane and has also specific transporters which allow absorption and reabsorption. These "tools" allows some substances like ions to be absorbed/reabsorbed (by the transporters), without any changes in the concentration of the other substances (because both the membrane and the transporters stopped them).</span>
You can figure it out by looking at a sequence of rocks to try to decipher the times that an event occurred relative to the other events represented in that sequence. The relative age of a rock then is its age in comparison with other rocks. If you know the relative ages of two rock layers, (1) Do you know which is older and which is younger? (2) Do you know how old the layers are in years? so yeah séquences haha
Oou do the one where you see which plants grows best in different lighting
More variation assists with survival. It increases the chance that at least some offspring of a parent survive.
