Normally cooks with microwaves emitting from a device in the microwave(sorry,I don't know the name of the device)
Biological or "Darwinian" fitness is being able to live long enough to reproduce and keep the population or species alive.
They are found in the body
The myelin sheath is the protective layer, which is present in the outer layer of the neural cells. This myelin sheath prevents the loss of electrical impulses, which are being conducted in the neurons. This also act as an insulator between neuron and its external environment.
This layer is mainly made up of the protein and fatty substance. The degeneration of the myelin sheath result in many neurological disorders.
Hence, the correct answer is myelin sheath.
Th answer is D its the best answer that fits the question .