Select the correct statements
(a) The most common form of prion disease that affects sheep is Creutfeldt-Jacob disease.
(b) A prion is a type of glycoprotein that can trigger normal proteins in the liver to fold abnormally.
(c) Prions attack nerve cells producing neurodegenerative brain disease.

In modern medicine certain infectious neurological diseases were found to be transmitted by an agent consisting of abnormally folded protein. These agents were called prions. The most notable diseases caused by prions are bovine spongiform encephalopathy (BSE) commonly called mad cow disease in cattle and its analogous variant Cr–Jacob disease (CJD) in humans. They attack nerve cells producing neurodegenerative brain disease.