The correct option is A.
The observation that the embryos of certain species have physical and genetical similarities in the earliest stages of embryonic development shows that individual development of an organism shows its revolutionary history and this is taken as an evidence of common ancestry. Scientists takes this observation to mean that all life on earth developed from a single ancestor.<span />
Answer: Option A.
nephron loop multiplies the concentration of salts in the interstitial fluid of the kidney medulla.
Explanation:
countercurrent multiplier is a system that utilize energy that create osmotic gradients and enable reabsorption of water thereby increase concentration of urine. The countercurrent multiplier uses electrolyte pumps there by making the nephron loop increase the concentration of salts in the interstitial fluid of the kidney medulla because it allows the nephron to reabsorb alot of water and and increase the concentration of urine for excretion while at the same time using as little energy as possible.
