Physical structures..........
Answer:

A society is choosing to replace its nuclear power plants with more sustainable geothermal power plants. Which of the following is an advantage to switching to geothermal power?
A. It can contaminate groundwater.
B. It uses a renewable resource.
C. It consumes a radioactive material.
D. It produces more hazardous waste.
Explanation:

Shivering occurs when the core temperature of the body begins to decrease which would threaten normal body function. Shivering is a response by the body to bring back temperature back to homeostasis. Trembling is the continual involuntary contraction of muscles. Muscle activity releases heat that warms up the body. This is the reason why we sweat during physical activities as the body sheds excess heat generated by the muscles in order to maintain the homeostatic body temperatures of 37 degrees centigrade.
I think it might be C I am not 100% sure though
C. employment and unemployment
because it is the only one that makes sense