What are the main contributors to "fatbergs" in sewer systems?

Fatbergs are large, solid masses that form in sewer systems, predominantly made up of solidified fats, greases, oils, and various non-biodegradable materials. These materials combine to create blockages that can severely disrupt wastewater flow.

The primary contributors to fatbergs are fats and oils, which are often washed down sinks or toilets, along with non-biodegradable items like wipes, plastics, and other solid waste that do not break down easily in water. The combination of these substances creates a thick, solid mass that can cling to the walls of pipes, leading to significant plumbing issues and sewage overflows.

In contrast, options focused on biodegradable materials, inert substances like sand and gravel, or organic waste do not contribute to the formation of fatbergs in the same detrimental way. While some organic waste can decompose and not contribute to blockages, grease and non-biodegradable materials are specifically responsible for the creation of fatbergs, making this the correct answer.