Which will most likely happen to cast iron connections during a fire?

During a fire, cast iron connections are likely to fail due to several factors related to the material properties of cast iron at elevated temperatures. Cast iron is known for its brittleness, which becomes more pronounced when exposed to intense heat. As the temperature increases, the structural integrity of the cast iron diminishes, leading to a potential failure of the connections between elements.

While cast iron does not expand uniformly like some other materials, the thermal stresses induced by uneven heating can cause cracks or fractures. The combination of thermal expansion and the inherent brittleness of cast iron under high temperatures is a critical concern in fire situations. This deterioration can lead to a loss of load-bearing capacity and, ultimately, the failure of connections that are essential for structural stability. Therefore, option B accurately captures the likely outcome for cast iron connections during a fire.