Answer: C- one should have high electron affinity and the other low ionization energy.
Explanation:
Ionization energy is the energy required to remove the electron from an isolated gaseous atom.
Electron affinity is the tendency of an isolated atom to attrcat the electrons towards itsellf.
An ionic bond is formed when an element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element or the metal and it can donate electron easily if it has low ionization energy.
The element which accepts the electrons is known as electronegative element or non metal and it can easily accept the electron if it has high electron affinity.
