Answer:
A. A metal atom loses electrons and a nonmetal atom gains electrons.
Step-by-step explanation:
An ionic bond is defined as the force of attraction between positive and negatively charged electrons.
An ionic bond is formed when a metal atom loses its electrons to atoms of a nonmetallic element. For example: Sodium Chloride (NaCl), where an atom of sodium (Na) donates an electron to an atom of chlorine (Cl) to form an ionic bond.
Hence, the correct answer is "A. A metal atom loses electrons and a nonmetal atom gains electrons."