Which of the following logic gates is a universal gate?

$A$ logic gate circuit has two inputs $A$ and $B$ and output $Y$. The voltage waveforms of $A, B$ and $Y$ are shown below. Identify the logic gate circuit.

Justify the output waveform $(Y)$ of the $OR$ gate for the following inputs $A$ and $B$ given in the figure.

To get an output $Y = 1$ in the given circuit,which of the following inputs will be correct?

The output $W$ for the given logic circuit is:

The following configuration of gates is equivalent to: