The answer is
letter A.
<span>
In the
evolutionary sense fitness refers to the measure of reproductive success of an
individual or of organisms in general. Those organisms that leave the largest
number of mature offspring are the fittest. Fitness can be achieved through survival
or mortality selection, mating success or sexual selection, and family size or
fecundity selection. Fitness is critical for a species’ survival and is a major
adaptation that all organisms do through a long period of time. <span> </span></span>
Answer:
<u>The Nephron</u>
The nephron is the functional unit of the kidney. The glomerulus and convoluted tubules of the nephron are located in the cortex of the kidney, while the collecting ducts are located in the pyramids of the kidney's medulla. ... The renal tubule is a long, convoluted structure that emerges from the glomerulus.
- libretexts
Our bodies produce an enzyme called lactase. This enzyme helps our bodies digest lactose (a sugar found in milk). As we age, the amount of lactase our bodies produce decreases. Some people don’t produce as much as others. If you are lactose intolerant, it means your body doesn’t produce a lot of lactase. One option is to drink milk with lactase added to it.
Example: Lactaid