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: Skin
Porphyrins are synthesized mainly in 
Select and explain. 
A. Spleen, B. Liver and spleen, C. Bonemarrow and spleen, D. Liver and Bone marrow
D: Liver and Bone marrow
Answer: D: Liver and Bone marrow 
Explanation: D i.e. Liver & Bone marrow