How to encrypt the truth table in garbled circuits?
Yao, encodes AND curcuit as;


the $x$ values as $k_x^0,k_x^1$,
the $y$ values as $k_y^0,k_y^1$,
the $z$ values as $z_k^0,z_k^1$.


Here the upper script represents 0 or 1.

\begin{array}{|c|}
\hline GCT \\\hline
  E_{k_x^0}(E_{k_y^0}(k_z^0))  &amp;  \\\hline
  E_{k_x^0}(E_{k_y^1}(k_z^0))  &amp;  \\\hline
  E_{k_x^1}(E_{k_y^0}(k_z^0))  &amp;  \\\hline
  E_{k_x^1}(E_{k_y^1}(k_z^1))  &amp;  \\\hline
\end{array}

Where $E$ is Symmetric Encryption Scheme, and in these schemes Block Ciphers can be utilized. One can use Asymmetric Encryption schemes but that will be slow, and non-standard.

so, given to keys, only one of the rows can be decrypted correctly.