Explanation
CompTIA covers it in page 97 of the comptia A+ complete study guide.

Explanation
A technician is working on a help desk ticket for a user who wants the filament replaced in a 3-D printer. To remove the old filament and load the new one, the technician should preheat the nozzle to melting temperature.
After the nozzle is heated, the technician should withdraw the filament and remove the spool. Then, cut a sharp angle on the end of the new strand, and push it along until resistance is felt.

Explanation
According to the Official CompTIA A+ Core 1 Study Guide (220-1101) , the correct answer is A. Document the findings, actions, and solution in the company knowledge base.
The explanation is that after resolving an issue, a technician should always document what was done and how it was fixed. This helps to create a record of the problem and its solution for future reference and also to share knowledge with other technicians.
https://www.comptia.org/training/books/a-core-1-220-1101-study-guide
By documenting the findings, actions, and solution in the company knowledge base, it will help to ensure that if the Issue happens again, the technician or a different technician will be able to quickly and easily find the solution and resolve the Issue. Additionally, it is important to document the solution so that the same Issue does not need to be troubleshot multiple times in the future.