Given a binary tree with the recursive implementation studied in this lesson, incicate what does the following method of LaTreeces class:

public int $f()$

if $($is Enpty$($o$)\}$

return ${}_{\text{;}}$

$?$

else

return $1$ ;

$\}$ else $\{$

return getleft $().f()+$getRight$().f()$;

$)$

Calculates the height of left and right subtrees.

Caiculates the height of the tree.

Calculates the number of nodes in the tree.

Caiculates the number of leaves in the tree.