Consider the binary search tree built by inserting the following sequence of integers,

one at a time: $5,4,7,9,8,6,2,3,1$

Which method below will properly remove node $4$ from the binary search tree?

Find the in order predecessor $($IOP$)$ of node $4,$ which is node $3.$ Remove node $3.$

from the tree by setting the right pointer of its parent $($node $2)$ to point to the node

pointed to by the left pointer of node $3.$ Then copy the key and any data from

node $3$ to node $4,$ turning node $4$ into a new node $3,$ and delete the old node $3.$

Set the left pointer of node $5$ to nullptr, and then delete node $4.$

Find the in order predecessor $($IOP$)$ of node $4,$ which is node $3.$ Remove node $3$

from the tree by setting the right pointer of its parent $($node $2)$ to nullptr. Then

copy the key and any data from node $3$ to node $4,$ turning node $4$ into a new node

$3,$ and delete the old node $3.$

Set the left pointer of node $5$ to point to the node pointed to by the left pointer of

node $4,$ and then delete node $4.$