In an AVL tree, if the balance factors at a given position are positive, we can make

A$.$ a single left rotation only

B$.$ a single right rotation only

C$.$ a double rotation

D$.$ either a single left rotation or a single right rotation

When it would be optimal to prefer Red$-$black trees over AVL trees?

A$.$ When there are more insertions or deletions

B$.$ When more search is needed

C$.$ When tree must be balanced

D$.$ When $log($nodes$)$ time complexity is needed