Which of the followings statements below are true about mast climbers?

I. The instability of the mast climber during dismantling is one of the common factors of incident when using a mast climber.

II. Mast climbers are quicker to erect and dismantle compared to scaffolding.

III. The risk of personal injuries, such as shoulder and lower back injuries, is reduced since a mast climber can be adjusted to an optimum working height.

IV. Mast climbers require more space on site than scaffolding.