The answer that best fits the blank provided above is C3a and C5a. Mast cells release this so called histamines once they are exposed to C3a and C5a which are fragments of complement proteins. These are also called as <span>Anaphylatoxins along with C4a. Hope this helps.</span>
The correct answer is option B, that is, functional group.
A functional group refers to a part of a molecule, which is a classified/recognizable group of bound atoms. The functional group provides the molecule with its characteristics, in spite of what molecule comprises it, they are the centers of chemical reactivity. The functional groups in a molecule require to be determined when naming.
So you know that your measurements are exactly correct.
Model two because it includes more organelles