The right answer is "C. Love is often demonstrated though personal sacrifice".
The explanation for this answer is in the excerpt "... when the armed guards board the bus, the mother leaves her son sleeping in the arms of a friend and lets himself be arrested." That is, this mother loved her son so much that she sacrificed herself so that he had the chance to have a better life.
When she allows herself to be arrested by the guards, her son has a chance to escape because the guards are already busy.