Answer:
The correct answer is C. Normal host cellular prion proteins (PrPC) are converted into scrapie proteins (PrPSc).
Explanation:
Prions are the infectious proteins that cause neurodegenerative diseases in both animals and humans. In humans, it causes various diseases like Creutzfeldt-Jakob disease, kuru. Collectively these diseases are called spongiform encephalopathies.
Humans contain normal cellular prion protein denoted as(PrPC) and the prions are abnormal form of this protein i.e., PrPSc where Sc indicates scrapie. This abnormal protein is misfolded form of normal prion protein.
When this misfolded prion protein enters the host body it converts all the normal cellular prion proteins in scrapie protein causing a fatal disease. In this disease, holes are created in the brain tissue and tissue degeneration gives brain appearance like sponges. Therefore the correct answer is C.