How do we decide which circuit is a latch?
To have a valid latch there must be three distinct values of the inputs:


One set of input values that forces the latch to a logic 1 state
One set of input values that forces the latch to a logic 0 state
One set of input values that holds the current state, whether it is 0 or 1


A valid latch circuit must also have an output signal, typically called Q, that reflects the stored state of the latch.

Set up the truth tables for each circuit and see if you can find the necessary input conditions for the circuit to be a latch.