Which means of securement is prohibited for securing metal coils with their eyes crosswise?

The correct answer is based on the regulations surrounding the transport of metal coils, particularly concerning securement practices. Securing metal coils with their eyes crosswise using direct tiedowns attached diagonally through the eye of the coil to form an X pattern is prohibited because this method can compromise the integrity and stability of the load during transit. The direct tiedowns may not hold the coils securely enough across different types of road conditions or during sudden stops, potentially leading to shifting or even falling of the cargo.

In contrast, the other securement practices mentioned, such as securing tiedowns parallel to the length of the coil or using indirect tiedowns attached to the vehicle sides, are acceptable. These methods provide a more stable and secure hold since they minimize the torque and lateral movement of the coils. Additionally, the use of friction mats serves to increase the grip between the load and the vehicle, which helps prevent movement during transport, making these options much safer for securing metal coils.