The correct option is A Ionic bond
Metals have a tendency to lose electrons while the non-metals have a tendency to gain electrons.
In a compound like NaCl, sodium (metal) loses an electron to chlorine (non-metal) and forms a bond known as an ionic bond. Since, an ionic bond is formed due to the electrostatic attraction between cation and anion hence it is also known as electrovalent bond. In this type of bond, an electron is completely transferred from one atom to another.