Had to look for the given illustration attached to this question and here is my answer. The site on the cross section provided wherein it is the most likely place for a spring would be SITE C. In the image, it is labeled sites A, B, C, and D. Hope this answers your question.
Answer:

Explanation:
The given data in the question is
Magnetic field : 
Turns : 
Length : 
So, number of turns per unit length :



If current is I , then magnetic field is given by

Also,

Insert the values


The current will be 
A distorted image. :3
hope i help
I think the answer is 3, population.