So white blood cell’s(WBCs for short) main job is to fight infections.
They do this by swallowing the infection.
You see,WBCs do not have a permanent shape.this means that they enlarge and decrease size of parts of their body.So they grow two long arm like structures called pseudopodia which swallow the infection.(pseudopodia means false feet).
You can see the process in the photo I attached from google
The heart is an example of an organ.
I will go with choice (C) density dependent pattern
Vegetables,Fruits,Nuts, ETC.
1) New Vaccines
4) Cancer drugs
5) Seedless grapes
...They all are the advantage of Genetic Engineering.