Answer
(a) electrons
Work Step by Step
Electrons are located in orbitals, or outer shells of atoms. They are the only subatomic particles that are not in the nucleus. The protons and neutrons are held in the nucleus. They have no role in reactions or chemical behaviors. The chemical makeup comes from the electrons, which can be moved between different atoms, gained, lost, or shared. Since the electrons are located outside of the nucleus, they have the ability to interact with other electrons of other atomsThis explains why the answer is not c) or d). Option b) is not a correct choice because an ion is not even a subatomic particle, it is a state that an atom can be in.
