The correct answer is option 3, decomposers.

Decomposers are microorganisms that play a crucial role in the nutrient cycle. They break down dead organisms and organic matter, such as leaves, animal waste, and dead plants, into simpler compounds. Through the process of decomposition, nutrients from these organic materials are returned to the ecosystem as inorganic nutrients. This allows the nutrients to be available for uptake by other organisms, such as plants or producers, which then use these nutrients for growth and development.

Producers (option 1) are organisms that can produce their own food through photosynthesis or chemosynthesis. Consumers (option 2) are organisms that obtain their energy by consuming other organisms.

Therefore, decomposers are specialized microorganisms that facilitate the recycling of nutrients in the atmosphere.