An open-ended cylinder of radius r and thickness t is subjected to internal pressure p. The Young's modulus for the material is E and Poisson's ratio is . The longitudinal strain is

• A. zero
• B. <img src="/_files/images/civil-engineering/strength-of-materials/140-6.215-1.png">
• C. <img src="/_files/images/civil-engineering/strength-of-materials/140-6.215-2.png">
• D. none of these.