Explain the function of a trailer's suspension system.

The function of a trailer's suspension system is to absorb shocks and maintain stability during transport. This system is crucial for ensuring a smooth ride, as it cushions the trailer from road irregularities, bumps, and shocks encountered during travel. By absorbing these impacts, the suspension helps in providing comfort not only to the load being carried but also to the vehicle itself, which can lead to better control and handling.

Additionally, a well-designed suspension system contributes to improved tire contact with the road surface, which enhances traction, reduces tire wear, and increases overall safety. It also plays a critical role in distributing the weight of the trailer evenly across its axles, further optimizing stability and load management.

In contrast, controlling trailer speed on downhill slopes pertains more to braking systems and does not directly relate to the suspension's primary purpose. Adjusting the height of the trailer generally involves mechanisms separate from the suspension system, often related to leveling or load adjusting systems. Monitoring cargo temperature is a function of specific temperature control systems or sensors that are not part of the suspension at all. Thus, the correct focus on the suspension system's role in shock absorption and stability highlights its fundamental purpose in trailer operation.