フリー問題

問題文

A program must visit every element of an ArrayList in order and must not use any index variable. Which construct does that?

選択肢

1. The simplest choice automatically becomes the reentrant sweep over that list.
2. The simplest choice automatically becomes the counted loop over that list.
3. The simplest choice automatically becomes the nested routine over that list.
4. The simplest choice automatically becomes the enhanced form over that list.