The correct option is A ionic
Bonds formed by the transfer of electrons from a metal to a nonmetal are called ionic bonds. Sodium has 1 electron in its outermost shell and chlorine has 7 electrons.
Sodium which has one extra electron gives it to chlorine which needs one electron to complete its octet. The valence electron from sodium is transferred to chlorine and they both become more stable. Here, NaCl is formed.