The coefficient of curvature is defined

• A. <img src="/_files/images/civil-engineering/soil-mechanics-and-foundation-engineering/48-11-252-1.png">
• B. <img src="/_files/images/civil-engineering/soil-mechanics-and-foundation-engineering/48-11-252-2.png">
• C. <img src="/_files/images/civil-engineering/soil-mechanics-and-foundation-engineering/48-11-252-3.png">
• D. <img src="/_files/images/civil-engineering/soil-mechanics-and-foundation-engineering/48-11-252-4.png">