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: Orthopaedics
Histological features of unicameral bone cysts are-a) Blood filled cystic spacesb) Endothelial cell liningc) Fibrous tissue with cystic spacesd) Pseudocyste) Single cavity with connective tissue lining 
Select and explain. 
A. a, B. b, C. ac, D. ce
D: ce
Answer: D: ce 
Explanation: Unicameral bone cyst is unilocular (single cavity cyst) with very thin connective tissue lining.
The lining of cyst consists of flimsy fibrous tissue, often containing giant cells, osteoclasts.
Cyst contains clear fluid.