The answer is natural killer cells.
Natural killer cells are a type of lymphocytes and they are important for the innate immune system. They recognise stressed cells much faster than other immune cells. Their response is rapid and usually only a few days after a viral infection. They also respond to <span>cancer cell </span>formation. While other immune cells can detect only those harmful cells that have specific markers on the surface of the cell membrane, natural killer cells can even detect those cells that miss markers for apoptosis.
The change in crab color is an example of Disruptive selection because two extreme colors were preferred over the more moderate color. Thus, the correct option for this question is D.
<h3>What is Natural selection?</h3>
Natural selection may be defined as the selection of a few individuals from any given population according to their favorable variations.
Disruptive selection occurs when environmental conditions changes in two different directions. Due to which variance increases in population.
Therefore, the correct option is D.
To learn more about Natural selection, refer to the link:
brainly.com/question/14385908
#SPJ1
If this is for the scientific process unit, the answer is passing laws to prevent certain types of scientific research. I know because I had this question in biology.
By the heat of the enegry
