Define the term electron affinity.
A. A negatively charged particle created when an atom or molecule gains one or more electrons
B. The amount of energy needed to remove 1 mole of electrons from 1 mole of ground-state atoms or ions in the gas phase
C. A relative measure of the ability of an atom to attract electrons in a bond to itself
D. The energy change that occurs when 1 mole of electrons combines with 1 mole of atoms or ions in the gas phase