A simply supported beam of span l and flexural rigidity EI, carries a unit point load at its centre. The strain energy in the beam due to bending is

• A. <img src="/_files/images/civil-engineering/upsc-civil-service-exam-questions/55-348-1.png">
• B. <img src="/_files/images/civil-engineering/upsc-civil-service-exam-questions/55-348-2.png">
• C. <img src="/_files/images/civil-engineering/upsc-civil-service-exam-questions/55-348-3.png">
• D. <img src="/_files/images/civil-engineering/upsc-civil-service-exam-questions/55-348-4.png">