This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Structure and function of protein, Subject name: Biochemistry
Signal pathways activate transcription factors for their transpo into the nucleus by all except 
Select and explain. 
A. Detachment of the transcription factor from a complexing protein can unmask a nuclear localisation signal, B. Phosphorylation of impoin protein increases its binding affinity for transcription factors, C. Phosphorylation of the transcription factor can increase its impoin binding affinity, D. Dephosphorylation of the transcription factor can increase its impoin binding affinity
B: Phosphorylation of impoin protein increases its binding affinity for transcription factors
Answer: B: Phosphorylation of impoin protein increases its binding affinity for transcription factors 
Explanation: Impoin carrier molecule is not activated Reference: Harper; 30th edition