B. All atoms have a dense central core called the atomic nucleus. Forming the nucleus are two kinds of particles:protons, which have a positiveelectrical charge, and neutrons, which have no charge. All atoms have at least one proton in their core, and thenumber of protons determines which kind of element an atom is.
C. Protons, neutrons, and electrons are the three main subatomic particles found in an atom. Protons have a positive (+) charge. An easy way to remember this is to remember that both proton and positive start with the letter "P." Neutrons have no electrical charge.