This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
Which of the following is involved in transpo of large molecules from cytoplasm to the cell nucleus?(2018) 
Select and explain. 
A. Calthrin, B. Caveolin, C. Flotillin, D. Impoins
A: Calthrin
Answer: A: Calthrin 
Explanation: Clathrin mediated endocytosis is responsible for the internalization of many receptors and the ligands bound to them--including, for example, nerve growth factor(NGF). Rafts and caveolae,are involved in cholesterol regulation and transcytosis. Ref:- Ganong, pg num:-46, 47