void stack: :do$()$

$\{$

for$($int $i=0$;$i$ topindex$|$; $i++)$

$\{$T temp$=$entry $[$i$]$;

entry $[i]=$ entry $[$topindex$-$i$-1]$ ;

entry $[$topindex$-1-$i$]=$temp;

$\}$

$\}$

What is this method do$?$

a$.$ Replace each item with next item value in the stack

b$.$ Reverse the stack

C$.$ Doesn't do anything

d$.$ Swap the first item with the last one in the stack