Final answer:
Using water is not acceptable for extinguishing an electrical fire due to the risk of electric shock; safer alternatives include specific fire extinguishers, sand, or non-conductive blankets.
Step-by-step explanation:
The method that is not acceptable for putting out an electrical fire is using water. This is because water is a good conductor of electricity, and using it on an electrical fire can lead to the risk of electric shock, which can be fatal. Instead, using a fire extinguisher rated for electrical fires (Class C in the US), using sand, or using a non-conductive blanket, if available, are safer alternatives.