This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cell Membrane and transpo protiens, Subject name: Physiology
Structurally the connexons are: 
Select and explain. 
A. Hexamers, B. Pentamers, C. Tetramers, D. Trimeric proteins
A: Hexamers
Answer: A: Hexamers 
Explanation: A connexon is composed of six integral membrane protein(Hexamers), having subunits called connexins. Ligand-gated ion channels are made up of pentameric proteins. Voltage-gated ion channels are made up of tetrameric proteins. G-protein, ENaC are the examples of trimeric proteins.