Wait this is highschool biology?!
Woah... thought it would be harder....
Anyways, see "micro" means really small, so small that your bare eyesight can't take it (or see it, I don't care). A microscope was meant to see things that our eyes can't. Since humans cant see microlife we use a microscope.
Mind Blown...
Blood is considered to be a tissue and it is part of the circulatory system.
The human circulatory system functions to transport blood and oxygen from the lungs to the various tissues of the body. The heart pumps the blood throughout the body. The lymphatic system is an extension of the human circulatory system that includes cell-mediated and antibody-mediated immune systems.
D :) try it at home or go to the forest and you will see tiny brown dots
<span>on the underside of some fern fronds - called sori. these contain big amount of spores.</span>
Definitely #2 is the answer
Letter D is the correct answer.
Disruptive selection, also known as diversifying selection, is a type of natural selection that drives a population apart. This type of selection is based on the variation of a trait in a population. For instance, Garter snakes that have a different coloration pattern behave in different manners when threatened.