This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous System, Subject name: Pathology
Rosenthal fibres are: 
Select and explain. 
A. Intranclear inclusions, B. Intracytoplasmic inclusions, C. Present extracellularly, D. Part of cell membrane
B: Intracytoplasmic inclusions
Answer: B: Intracytoplasmic inclusions 
Explanation: Ans. (b) Intracytoplasmic inclusions(Ref: R 9th/pg 1253)Rosenthal fibers-*Brightly eosinophilic structures/inclusions within cytoplasm of Q astrocytic processes*Contain two heat-shock proteins (aB-crystallin and hsp27) as well as ubiquitin Q*Seen in Alexander disease, pilocytic astrocytoma Q.