Based on the modes of nutrition, bacteria that serve the role of decomposers in the environment are categorised as

Explanation

Decomposers play a crucial role in ecosystems by breaking down dead organic material and recycling nutrients. These organisms are classified as chemoheterotrophs because they obtain their energy and carbon from organic compounds, which they decompose. In contrast, photoautotrophs and chemoautotrophs derive their carbon from carbon dioxide and not from decomposing organic matter. Photoheterotrophs use light for energy but, like chemoautotrophs, are not primarily decomposers.