Which statement best describes the oxidation numbers of the atoms found in magnesium chloride?

A. Magnesium has a 2- oxidation number and chlorine has a 1+ oxidation number.
B. Magnesium has a 2- oxidation number and chlorine has a 2+ oxidation number.
C. Magnesium has a 2+ oxidation number and chlorine has a 1- oxidation number.
D. Magnesium has a 1+ oxidation number and chlorine has a 1- oxidation number.