Answer: Option (a) is correct.
Step-by-step explanation:
It is known that electrons hold a negative charge. So, when the negative charge that is electrons are taken out an atom then the number of electrons become less in number as compared to the number of protons.
Hence, the atom attains a positive charge.
An isotope is formed when an atom shows same number of protons and different number of neutrons. So, when an atom loses 2 electrons there will be no change in the number of neutrons. Therefore, an isotope will not form.
Thus, it is concluded that when an atom with no charge loses two electrons, it becomes a positive ion.