Final answer:
Feature (d) 'All the planetary orbits are highly elliptical and not in the same plane,' contradicts the nebular theory because it suggests a chaotic origin, whereas the theory predicts near-circular orbits within the same plane.
Step-by-step explanation:
The nebular theory of planet formation describes how stars and planets form from a rotating cloud of interstellar gas and dust, called a nebula. According to this theory, as the nebula collapses, it flattens into a disk with the star forming at the center. Planets then form from this protoplanetary disk, acquiring orbits that are roughly circular and coplanar, meaning they are in the same plane as the disk itself.
Feature (d), 'All the planetary orbits are highly elliptical and not in the same plane,' would contradict the nebular theory. If all the planetary orbits of a solar system are highly elliptical and not in the same plane, it suggests a more chaotic origin that doesn't align with the orderly fashion described by the nebular theory, where planets are expected to have near-circular orbits in the same plane due to the conservation of angular momentum in the original collapsing nebula.