Which one of the following substances possesses the highest elasticity?

$A$ truck is pulling a car out of a ditch by means of a steel cable that is $9.1 \, m$ long and has a radius of $5 \, mm$. When the car just begins to move,the tension in the cable is $800 \, N$. How much has the cable stretched? (Young's modulus for steel is $2 \times 10^{11} \, N/m^2$)

$A$ rubber cord $10\, m$ long is suspended vertically. How much does it stretch under its own weight? (Density of rubber is $1500\, kg/m^3$,$Y = 5 \times 10^8\, N/m^2$,$g = 10\, m/s^2$)

$A$ fixed volume of iron is drawn into a wire of length $l$. The extension produced in this wire by a constant force $F$ is proportional to

On increasing the length by $0.5\, mm$ in a steel wire of length $2\, m$ and area of cross-section $2\, mm^2$,the force required is ($Y$ for steel $= 2.2 \times 10^{11}\, N/m^2$).

In Young's experiment,if the length of the wire and the radius are both doubled,then the value of $Y$ will become: