Answer: B.They are arranged in energy levels
Explanation: Electrons orbit around the nucleus of an atom, and are not spread around equally throughout an atom because there are a different amount of electrons that can fit in each energy level or electron shell (both are the same thing). For example the first energy level can hold up to 2 electrons, the second shell can hold up to 8 electrons, the third can hold up to 18, and so on represented by the equation 2(n^2)