पुढील दोन विधानांपैकी कोणते अयोग्य आहे ?
(a) क्रूजफ्रेल्ड-जेकब हा मेंदूचा विकार प्रथिनांमुळे होतो.
(b) त्यांच्यात न्युक्लिक आम्लं नसते व त्यांना प्रायॉन म्हणतात.
पर्यायी उत्तरे :

The correct answer is Option D (Neither).

Key Points:
• Prion Biology and Creutzfeldt-Jakob Disease (CJD):
• Discovered by Nobel Laureate Stanley B. Prusiner in 1982, Prions are unprecedented infectious pathogens causing Transmissible Spongiform Encephalopathies (TSEs) like Creutzfeldt-Jakob disease (CJD) and Mad Cow Disease (BSE).
• Scientific Characteristics:
• Statement (a) is correct: CJD is a fatal neurodegenerative disorder caused by misfolded conformational forms of the normal cellular prion protein (PrP^C rightarrow PrP^Sc) causing spongy brain degradation.
• Statement (b) is correct: Prions are entirely proteinaceous infectious particles devoid of any nucleic acid (neither DNA nor RNA).
• Because both statements are scientifically sound, neither statement is incorrect.
• Hence, Neither (Option 4) is the keyed answer.
• Key Takeaway: Creutzfeldt-Jakob disease is caused by prions—abnormal misfolded proteins completely devoid of nucleic acids (DNA/RNA).