I actually haven't understood the question itself only...I am not able to draw out any figure reading this question...that's my actual problem 

The thread experiences a force radially outwards and parallel to the film. The loop assumes a circular form, as shown fig. This is because, for a given perimeter, a circle encloses the maximum area, and hence the film surroundings the loop tends to assume the least area.

source: https://www.aspirebuzz.com/content/thin-loop-thread-floats-soap-film-f