What does the binary search tree below look like after I remove $18?$

$6,\frac{?}{\frac{?}{?}}\frac{?}{?}$

$4,10\frac{?}{\frac{?}{?}}$

$,1$

$8,12$

None of the choices.

$12$

$11$

$610$

$/$

$48$

$10$

$/1$

$612$

$/$

$48$