Explanation:
There are only two inputs to the circuit, and one output. There is an internal signal, not an input, between the inverter and the AND gate.
Here, it is convenient to label the top input A, the inverter output B, and the bottom input C. Of course, the output is labeled D.
Then B is the logical inverse of A, and D is the AND of B and C.
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<em>Check for you</em>
D will only be 1 for A=0 and C=1. It will be 0 otherwise.
