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
Steroid receptor regulatory protein: 
Select and explain. 
A. Zinc finger, B. Heliz-turn -helix, C. Leucine zippor, D. RNA
A: Zinc finger
Answer: A: Zinc finger 
Explanation: A i.e. Zinc finger