Question $4$

$3\mathrm{.}6pts$

Suppose $x$ and $y$ are both pointers to integers. The goal of the program is to swap the addresses of the two pointers. For example, if $x$ is initially storing the hexadecimal address $x0001,$ and $y$ is initially storing the hexadecimal address $x0002,$ after the program is finished $x$ should be storing $x0002$ and $y$ should be storing $x0001.$

Which of the options below is the correct implementation of the program?

$$ int ${?}^{**}$ temp $={?}^{**}x$;

int ${?}^{**}$ temp $=x$;

$x=y$;

$y=$ temp;

int ${?}^{**}$ temp $=$&$x$

${?}^{**}x=$&$y$;

${?}^{**}y=$ &temp;

int ${?}^{**}$ temp $=$&$x$;

$x=$&$y$;

$y=$ &temp;