Final answer:
The statement that most planets discovered around other stars are more massive than Jupiter is false. Kepler's discoveries indicated that there are more smaller, Earth-sized planets and planets with varying sizes called 'super-Earths' and 'mini-Neptunes'. Large planets several times more massive than Jupiter exist but are less common.
Step-by-step explanation:
Most of the planets discovered around other stars are not more massive than Jupiter. This statement is False. The initial discoveries using the Doppler technique found many giant planets, termed 'hot Jupiters', because they were the easiest to detect. However, Kepler's discoveries reveal that there are actually more rocky, Earth-size planets and a variety of planets with sizes and masses that differ from those in our solar system. The most common exoplanets discovered have radii between 1.4 and 2.8 times that of Earth, often referred to as 'super-Earths'. Additionally, a significant number of planets have been found with sizes between 2.8 and 4 times that of Earth, which are sometimes called 'mini-Neptunes'. There is also the discovery of planets that are several times more massive than Jupiter, though these are less common than smaller planets.