A thread is tied slightly loose to a wire frame as in figure and the frame is dropped into a soap solution and taken out. The frame is completely covered with the film. When the portion A is punctured with a pin, the thread   

• A

   Becomes concave towards A

• B

  Becomes convex towards A

• C

  Either (a) or (b) depending on the size of A with respect to B

• D

  Remains in the initial position