In the search for extra-solar planets the technique listed that has found the most planets uses Question 40 options: a) changes in the emission spectrum of the star due to the additional emission lines from the planet. b) the Doppler shift of the star to detect the wobble in the stars motion caused by the presents of a planet. c) direct observations of the planets. d) direct observations of the side-to-side motion of the star caused by the presence of a planet