Final answer:
The orbit of Pluto is more eccentric than the orbit of Mercury. Pluto's orbit is not only more elongated and elliptical than Mercury's, but it also deviates from the common plane of the major planets of the solar system.
Step-by-step explanation:
The object's orbit which is more eccentric than the orbit of Mercury is D) Pluto. Eccentricity is a measure of how an orbit deviates from being circular. The more eccentric an orbit is, the more it is elongated and elliptical. While Mercury has a very eccentric orbit, with an eccentricity of 0.21, the orbit of Pluto is even more eccentric. Pluto’s orbit is inclined about 17° to the ecliptic, which is the plane of Earth's orbit and it deviates considerably from the common plane of the major planets of the solar system.
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