Nancy took a breath and gathered her thoughts. She imagined that passing through the gray-zone door into Level 4 was like a space walk, except that instead of going into outer space, you went into inner space, which was full of the pressure of life trying to get inside your suit. People went into Level 4 areas all the time at the Institute, particularly the civilian animal caretakers. But going into a containment zone to perform a necropsy on an animal that had died of an amplified unknown hot agent was something a little different. This was high-hazard work. –The Hot Zone, Richard Preston What is the central idea of this excerpt from The Hot Zone?
A. animal necropsies are done only by trained professionals.
B. People go into Level 4 areas all the time at the Institute.
C. Entering Level 4 is like going into inner space.
D. Working in a containment zone is very dangerous.

The correct answer is D. Working in a containment zone is very dangerous.

Explanation:

The excerpt from "The Hot Zone" describes the thoughts of a female character called Nancy as she needs to get to a Level 4 zone (highest level in biosafety zones) and work in this. During the excerpt, the narrator shows how the narrator perceives this place as dangerous and is quite worried about this. This can be seen in "which was full of the pressure of life trying to get inside your suit" that shows how Nancy is afraid of getting infected with a bacteria, virus or pathogen in the zone, or in "This was high-hazard work" that shows the apprehension of Nancy for the zone and the work she has to do in there. Thus, the central idea or point is "Working in a containment zone is very dangerous".

the statement flat characters usually only have one trait that is developed in their story lines is true.

it is true my friend