Answer:
a
Explanation:
the answer should be that
It is definitely not a primary source: this would be a book itself.
Now, is it a tertiary source? I don't think so: the author of the review should have read the book and should only be referring to this book in the review.
I think it's a secondary source.
Answer;
-Special stains
Explanation;
-Cell staining is important in the diagnosis of microorganisms because bacteria can be identified by the color differentiation of stains (dyes).
-Microscopic examination of stained cell samples allows examination of the size, shape, and arrangement of organelles, as well as external appendages such as the whip-like flagella, which are the cell's organs of motion. When sample cells are stained to show their chemical composition it is called differential staining.
-Special stains are used to help visualize and/or identify structures and substances in sections.
Its in a way both C and D as at cholesterol acts as a fluidity buffer that at high temps. the cholesterol makes the membrane less flexible and at lower temps. makes the membrane more fluid
Sorry Hope that helps though