Final answer:
The statement about the composition of an atom that could not be inferred from Rutherford's experiment is that electrons do not orbit the nucleus in a planetary motion.
Step-by-step explanation:
The Rutherford gold foil experiment led to the discovery that atoms consist of a tiny, dense nucleus surrounded by electrons that occupy the space around it. Rutherford deduced that since most alpha particles passed straight through the gold foil, the atom was mostly empty space, with a centrally concentrated positive charge in the nucleus. The key finding from this experiment was the presence of the small but dense positively charged nucleus.
The statement that could not be inferred from Rutherford's experiment is A) Electrons do not orbit the nucleus in a planetary motion. His model suggested electrons orbit like planets around the sun, which was later found to be inaccurate with the development of quantum mechanics. The other options B) The nucleus of the atom is small compared to the size of atoms, C) The atomic nucleus has a positive charge, and D) The atom is mostly empty space, are all correct inferences from his experiment.