A physical property of concrete is its resistance to

• A. Chemical attack
• B. Density
• C. Fire
• D. Color

Answer: (C)

Fire resistance is about how well a material withstands exposure to heat and fire without losing its structural capacity. Concrete isn’t combustible and has significant thermal mass, so it slows heat transfer and helps protect reinforced elements for a period of time. That makes it resistant to fire, which is why this choice is the best fit for describing a concrete property. The other options describe different ideas: chemical attack refers to deterioration from chemicals (a durability/chemical aspect), density is a basic material property but not a resistance to something, and color isn’t related to resisting heat or fire.