What is the most logical next event?

An introduction comes onto the screen for a video about home repair. two men on a roof

Select from: (I) are trying to fix a leak in a pipe located on top of the roof.; (II) are using roofing materials to move tiles to the side of the roof using a steel plate and peser machine.; (III) are preparing to put on some roof well dger-letch roofing beams, and the contractor reminds them that they're doing it outside on the yard roof.; (IV) are shown in a company garage, working to repair and replace old roof tiles.;
(I)