After Malaysia Airlines flight MH730 disappeared, the INMARSAT crew calculated the whereabouts of the missing flight using the Doppler principle. The Doppler principle is derived from such a physical phenomenon (Doppler effect): As the aircraft approaches at high speed ( (Or away) satellites that receive microwave signals, the microwave frequencies detected by the satellites will become higher (or lower). Which of the phenomena described below reflects the same Doppler effect? ['People standing near the railroad tracks hear the whistle of a train coming from far away and into the highway at high speed.', 'A beam of natural light enters the prism, and when it is emitted, it is broken down into different colors.', 'A small pebble is thrown into the calm lake water, and the ripples spread in a circle and gradually spread to the surroundings.', 'During the solar eclipse, the existence of sunspots was observed.']