Answer:
B. The atom loses 1 electron, to make a total of 18.
Explanation:
Since proton lies inside the nucleus of the atom so it is bounded strongly by the nuclear forces
So it is very difficult to charge an atom by transfer of protons as it need to work against nuclear forces
But electrons orbit around the nucleus in different energy state so all those electrons which are lying at the outermost orbit is loosely bound and hence it is easy to remove that electron.
Since potassium ion has atomic number 19
so for a neutral ion it has 19 electrons and 19 protons in it
now in order to make it a charge of +1
so we can remove one electron from it so that it has 19 protons and 18 electrons it so due to which it will have +1 charge on it
so correct answer will be
B. The atom loses 1 electron, to make a total of 18.