with pass transistor logic.

This implementation uses two transmission gates and two inverters not shown in the diagram to generate and for a total of eight transistors, four less than in the previous design. The XOR function is implemented by passing through to the output the inverted value of A when B is high and passing the value of A when B is at a logic low. so when both inputs are low the transmission gate at the bottom is off and the one at the top is on and lets A through which is