For Some Representative Metals, Two Possible Ions Can Be Formed

Multiple Choice

For some representative metals, two possible ions can be formed. Why?

A) s electrons can fill the next lower d orbital.
B) They can lose electrons to form a cation and gain electrons to form an anion.
C) They can lose the s electrons or all electrons in their outer shell.
D) They can lose just the p electrons or all electrons in their outer shell.