Question $20/1$ ptstsSuppose that you are asked to analyze the Big$-$Oh of the following methodpop. What pieces of additional information which need to give a perfectlyaccurate answer? Select all that apply.public ItemType pop$()\{$if $($isEmpty$())$throw new NoSuchElementException$()$;ItemType element $=$ top.getElement $()$;top $=$ top. getNext $()$ ;n$--$;return element;