Why should tankers be parked on flat ground whenever possible?

Answer: B — To prevent rollaway incidents and ensure stability

Parking tankers on flat ground is essential for several reasons, predominantly to prevent rollaway incidents and ensure stability. Tankers, especially when loaded with liquid cargo, have a high center of gravity and can be particularly unstable on sloped surfaces. When a tanker is parked on an incline, the liquid inside may shift, creating a risk of tipping or rolling, which can lead to dangerous accidents. In contrast, parking on flat ground minimizes the risk of movement, as the weight of the load is evenly distributed, maintaining the vehicle's balance. This is critical for safety, as even a slight gradient can initiate downhill movement, especially if the brakes were not fully engaged. Ensuring that a tanker is on level terrain not only protects the vehicle but also safeguards personnel and the surrounding environment from potential spills and accidents. Thus, the correct answer emphasizes the importance of stability and safety when dealing with these sensitive vehicles and their cargo.