This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: general microbiology, Subject name: Microbiology
Growth on a cell-free aificial solid medium is possible for following except - 
Select and explain. 
A. Ureaplasma urealyticum, B. Mycoplasma Pneumoniae, C. C & L form of proteus vulgaris, D. Chlamydia
D: Chlamydia
Answer: D: Chlamydia 
Explanation: They are bacteria but may be considered as viruses on account of their filterability and failure to grow in cell-free culture media. REF: Textbook of microbiology Ananthanarayan, and Paniker. Page no.: 415