(4) D
We have extension = ΔL = FL/AY = FL/πr2Y
For the same load extension in proportional to L/r2Y.
In other words the extension depends on the value of L/r2Y of the wires. We have, the values of L/r2Y in the following table.
![](https://www.sarthaks.com/?qa=blob&qa_blobid=2379986789204100613)
As the value is maximum for D; the extension will also be maximum in D.