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: Pharmacology
All of the following have receptors which are transcription factors except - 
Select and explain. 
A. Insulin, B. Estrogen, C. Glucocoicoids, D. Vit D
A: Insulin
Answer: A: Insulin 
Explanation: Ans. is 'a' i.e., Insulin Transcription factors are intracellular (cytoplasmic or nuclear) soluble proteins which respond to lipid soluble chemical messengers that penetrate the cell. o All steroidal hormones (glucocoicoids, mineralocoicoids, androgens, estrogens, progesterone), thyroxine, vit D and vit Afunction in this manner.