A

Some devices that are used for temporary work zone situations are cones, barricades, drums, arrow panels, flags, pavement markings, and orange and black work zone signs.

Explanation:

The main purpose of these devices is to warn drivers and pedestrians of danger and make them pay attention to the road. Some of the objects are also used to prevent people from entering the area since it may disturb workers or put the trespassers at risk.

There are different types of work zone situation devices. Delineation devices such as posts, traffic cones, and flexible drums separate traffic to let cars choose the safe way to go around a work site.

Barricades, highly visible warning devices such as rumble strips, are used to block people from entering an activity area. Lastly, temporary condition working signs are installed in advance with the purpose to convey information to passers-by.

Orange work zone signs on the road.
Source: https://reflectives.averydennison.com