Answer:
A, B and C
Step-by-step explanation:
When talking about a computer or laptop charging, there are ONLY 3 things that matter.
The Battery - This is where the electricity or "wall juice" is stored.
AC Adapter - This is how the Battery gets its juice, it plugs into the computer itself.
LCD Power Adapter - This plugs into the wall to pull the electricity from the grid into your computer passing through AC Adapter.
On a side note... the most logical reason the computer could not be going over 15% nor charge anymore than 30mins is because the battery has been shortened by either a storm or a power surge.