Which type of wiring method could provide a flexible connection to equipment subject to settlement?

The option regarding direct burial wiring is particularly relevant when considering a flexible connection to equipment that may be subject to settlement. Direct burial wiring is specifically designed to be buried underground without the need for additional conduit or raceway. This method can accommodate slight movements in the ground or the installation site, which can occur due to natural settling or shifting.

Direct burial cables are constructed with robust insulation and protective layers that enable them to withstand the pressures and conditions of being underground. They are typically rated for such applications and are treated to resist moisture and corrosion. Thus, if the equipment to which these wires are connected experiences movement, the direct burial method allows for some degree of flexibility without compromising the integrity of the electrical connection.

Other wiring methods, such as raceway wiring and conduit wiring, are typically rigid and may not provide the same level of adaptability to movement or settling as direct burial wiring can offer. While these methods are valuable for protecting wiring in other applications, they do not lend themselves as well to situations where flexibility is necessary due to the potential for ground movement. Open wiring, while flexible in some contexts, typically would not be suitable for underground applications or where conditions of settlement are anticipated, making direct burial a more appropriate choice in this case.