They are part of an organ system
The correct answer is D.
An internal pressure that will most likely create conflict would be disagreeing about which school kids should attend. An internal pressure is one that is found amongst the family members and affects them all. Due to Andy losing his job and them having to relocate with extended family members the chances are that the options for schools for the kids would cause disagreement because there are now other factors to consider like influences from extended family members, the local area schools which are the only choice for their kids now and which might not be good schools, they more than likely can't afford to home school and so forth.
Plasma is a pale-yellowish<span>, watery solution that suspends all of the other parts of the blood. It makes up about 55% of the total volume of our blood. Plasma itself is made up of 91.5% water. It acts as a solvent for important proteins, nutrients, electrolytes, gases, and other substances essential to life.</span>
None really unless you are talking about an animal