This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Osteoporosis, Sex Hormones and OCPs, Subject name: Pharmacology
All of the following agents act through nuclear receptors EXCEPT: 
Select and explain. 
A. Thyroxine, B. Rosiglitazone, C. Prednisolone, D. Estrogen
C: Prednisolone
Answer: C: Prednisolone 
Explanation: Prednisolone (coicosteroids) acts through cytoplasmic receptors whereas thyroid hormones (T3, T4), retinoids (vitamin A) and thiazolidinediones (like rosiglitazone) have nuclear receptors.