The correct answer is D.
Excessive charging a battery tends to produce gassing, increase the internal resistance of the battery, and to corrode the positive plates into lead peroxide thereby weakening them physically.
Gassing is the formation of hydrogen and oxygen gases inside the battery. This can cause the battery to swell and can also lead to the formation of leaks.
Increased internal resistance means that the battery is less efficient at storing and releasing energy. This can lead to a shorter battery life and can also cause the battery to overheat.
Corrosion of the positive plates can weaken the battery and can also lead to a shorter battery life.
All of these changes can damage the battery and can shorten its lifespan. It is important to avoid overcharging a battery to prevent these problems.