Which of the following statements is true?

a. protons are located outside the nucleus of an atom.
b. individual atoms can be seen with the naked eye.
c. the nucleus of an atom contains protons and neutrons.

The correct answer is C. Atoms are incredibly small and can bearly be seen with the most powerful electron microscopes. The nucleas of an atom contains protons and neutrons with electrons in orbitals around the nucleas. I hope this helps. Let me know if anything is unclear.