Let A {1,2, 3,4} and let R {(1,1),(1,3),(2,4).(2,2)} , then the symmetric closure of R is
{(1,1),(1,3),(2,2),(3,1)}
{(1,1),(1,3),(2,4),(2,2),(3,1),(4,2}}
{(1,1),(1,2),(2,2),(2,4),(2,2),(1,3),(3,1),(4,2)}
{(1,1),(1,3),(2,4),(3,1).(4,2),(2,2),(3,3),(4,4)}