A) 0

B) 0.25**C) 0.5**

D) 1

According to IS 456:2000, Clause 6.2, **Poisson’s ratio is defined as the ratio of transverse strain to axial strain. For a material that does not change in volume under stress, the transverse and axial strains must be equal in magnitude but opposite in sign. Therefore, the Poisson’s ratio for such a material must be 0.5.**

Table 6 of IS 456:2000 provides typical Poisson’s ratio values for common materials used in concrete structures. For example, the **Poisson’s ratio for structural steel is 0.3 and for concrete is 0.2.**

**The correct option is C) 0.5**

This indicates that the material is incompressible and does not change volume when loaded in one direction. Rubber exhibits such behavior and has a Poisson’s ratio of around 0.5.