Final answer:
The safest storage option for bleach-based cleaning solutions in a childcare facility is in a locked cabinet placed out of reach of children to prevent accidental poisoning or contact.
Step-by-step explanation:
The best place for Sofia to safely store the bottles of bleach-based cleaning solutions to ensure her childcare facility remains childproofed is in a locked cabinet out of reach of children. This method of storage prevents accidental ingestion or contact by children, thus avoiding any potential harm or poisoning. It is important for Sofia to maintain stringent safety protocols, especially where children are involved, to prevent unintended access to hazardous materials.