Which type of conduit is not suitable for forming shallow curves?

The correct choice indicates that Type E conduit is not suitable for forming shallow curves due to its rigidity and structural design. It is typically constructed from materials that are not flexible enough to easily bend without breaking or kinking, which means it would struggle to accommodate installations requiring shallow curves without risking damage or hindering performance.

In contrast, Type D, Type A, and Type B conduits usually possess greater flexibility or are designed to manage curves effectively. These types can accommodate shallower bends allowing for smoother transitions and help reduce stress on the cables running within, which is crucial for maintaining signal integrity and longevity of the installation.

Understanding the specific properties of each conduit type is essential for selecting the right one based on the installation requirements, ensuring that cables are protected adequately and functionality is maintained.