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: Biochemistry
The colour vision is governed by all of the following colour sensitive pigments EXCEPT:- 
Select and explain. 
A. Porphyropsin, B. Transducin, C. Iodopsin, D. Cyanopsin
B: Transducin
Answer: B: Transducin 
Explanation: The colour vision is governed by colour sensitive pigments-porphyropsin (red), iodopsin (green) and  cyanopsin (blue).
Reference: Satyanarayana- Biochemistry, 3rd edition, pg-122