Anaesthetic circuit that prevents rebreathing of CO2 –

You all know, amongst the given options only circle system is rebreathing system. It is quite obvious, CO2 must be eliminated from the exhaled air before rebreathing to prevent hypercapnia. Therefore, rebreathing system has a CO2 absorbent that absorbs CO2 and prevents CO2 rebreathing. Don’t get confuse by name (rebreathing system), there is rebreathing of exhaled gases after absorption of CO2.