Which of the following properly handles the side effects in this function?public String sequence$($BSTNode node$)$if$($node $!=$ nu$11)$return node. getData$)$ toString$()+$ sequence $($node$-$getLeftchild$())+$ sequence $($node$.$ getRightchild$())$;elsereturn $"-"$;$\}$ This function is fine the way it is$.$ There are no side$-$effects. Change the function to public String sequence$($BSTNode node, String nodeString$)$The toString method can't be trusted We should be assigning values to a string variable to act as an accumulator and return it when its done. getData is unknowable and could be considered a hidden input There aren't any hidden inputs or side effects, but the recursion is wrong and wont work.