This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
Prions include: 
Select and explain. 
A. DNA and RNA, B. Only RNA, C. Proteins, D. Only DNA
C: Proteins
Answer: C: Proteins 
Explanation: Answer is C (Proteins): Prions are infectious proteins devoid of any nucleic acid (RNA or DNA)