Correct Answer - Option 4 : 0.45

**Concept:**

Engineering strain: It is the ratio of change in dimension to the original dimension.

ϵe = \(\frac{{{\rm{\Delta }}L}}{L_0}\)

True strain: It is the ratio of instantaneous elongation to the instantaneous dimension.

\({\epsilon_t} = \ln \left( {\frac{{{A_0}}}{{{A_f}}}} \right)\)

**Calculation:**

**Given:**

d_{o} = 5 mm,d_{f} = 4 mm

⇒ \({\epsilon_t} = \ln \left( {\frac{{{A_0}}}{{{A_f}}}} \right) = 2\ln \left( {\frac{{{d_0}}}{{{d_t}}}} \right) = 2ln\left( {\frac{5}{4}} \right) = 0.446\)