This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Biochemistry
Which of the following belongs to steroidal receptor superfamily? 
Select and explain. 
A. Vitami D3, B. Encephalins, C. GH, D. Insulin
A: Vitami D3
Answer: A: Vitami D3 
Explanation: Biological actions of vitamin D are now considered to be exeed through the nuclear vitamin D receptor (VDR)-mediated control of target genes.VDR belongs to the nuclear hormone receptor superfamily and acts as a ligand-inducible transcription factor.Ref: DM Vasudevan, 7th edition, page no: 667