In an atom, the nucleus contains?

• A. Protons and neutrons
• B. Electrons
• C. Quarks
• D. Molecules

Answer: (A)

The nucleus contains protons and neutrons, together called nucleons. Protons carry positive charge, neutrons have no charge, and their combined mass makes the nucleus dense and a small, central region of the atom. Electrons sit outside the nucleus in orbit around it, held by the electrostatic attraction to the protons. Quarks are the smaller particles inside protons and neutrons, not separate components of the nucleus itself. Molecules are groups of atoms bonded together, not parts of the nucleus.