A swollen battery is the most likely cause of the issue that the customer is reporting. A swollen battery is a battery that has expanded in size due to a chemical reaction, gas buildup, or overheating. A swollen battery can cause pressure on the laptop's chassis, keyboard, track pad, and other components, making them hard to press or click. A swollen battery can also pose a fire hazard and damage the laptop's performance and lifespan.
The other options are not as likely or relevant to the issue. Dropping the laptop may cause cracks or other visible damage to the chassis or screen, but the technician did not notice any. The digitizer is the part of the laptop that converts touch input into digital signals, and it has nothing to do with the keyboard or the track pad buttons. An open bottle of rubbing alcohol falling onto the keyboard may cause liquid damage, corrosion, or short circuits, but it would not affect the track pad buttons or the bottom edge of the keyboard.
To troubleshoot and resolve the issue, the technician should remove the battery from the laptop and inspect it for signs of swelling, such as bulging, deformation, or leakage. The technician should also check the laptop's chassis, keyboard, and track pad for any signs of damage or warping caused by the battery. The technician should then replace the swollen battery with a new one that is compatible with the laptop's model and specifications. The technician should also dispose of the swollen battery properly and safely, following the local regulations and guidelines.
References:
* CompTIA A+ Certification Exam Core 1 Objectives1
* The Official CompTIA A+ Core 1 Student Guide (Exam 220-1101) eBook2
* How to Fix a Swollen Laptop Battery - Lifewire3
* How to Tell If Your Laptop Battery Is Swollen - Techwalla4