20.Which of the following will become a negative ion when it bonds with another atom?Select one:a. Ab. Bc. Cd. D

Option A is correct.
Elements that becomes a negative ion when it bonds with other atoms are mostly non-metals. Therefore elements such as nitrogen, oxygen, fluorine, chlorine tends to form a negative ion when bonded with other atoms.
This elements also tends to accepts electrons to complete their outer shells. From the given diagram, we can see that the element with 8 protons is oxygen and a non metal. Hence, the element A will become a negative ion when it bonds with another atom