Answer :
The answer is B- they have one overall charge. Atoms are neutral, meaning they contain the same number of protons as electrons. When you remove an electron from this atom you get a positively charged ion that has a net charge of +1. By adding an electron, however, you get a negative charge on the ion.
Answer : The correct option is, They have one overall charge.
Explanation :
All the ions must have one overall charge that means the charge on ion can either a positive or a negative.
They are made of one type of atom : This statement is incorrect because the ions can be made of one or more types of atoms also.
They have two or more overall charges : This statement is incorrect because the charge on ions can either be a positive or a negative.