Organisms which are predominantly found living on, in or near bed sediments of rivers or lakes are known as

The correct answer is C. Benthic.

Benthic organisms are those that live on, in, or near the bottom of a body of water. They can be found in both marine and freshwater environments. Benthic organisms include algae, bacteria, fungi, invertebrates, and fish.

Benthic organisms play an important role in the food chain. They are a source of food for other organisms, and they help to recycle nutrients. Benthic organisms are also important in the process of sediment formation.

There are many different types of benthic organisms. Some of the most common types include:

• Algae: Algae are simple, plant-like organisms that can be found in both marine and freshwater environments. They are a major source of food for other organisms.
• Bacteria: Bacteria are single-celled organisms that can be found in all environments, including water. They play an important role in the decomposition of organic matter.
• Fungi: Fungi are multicellular organisms that can be found in both soil and water. They play an important role in the decomposition of organic matter and the cycling of nutrients.
• Invertebrates: Invertebrates are animals that do not have a backbone. They include a wide variety of organisms, such as worms, insects, and mollusks. Many invertebrates are benthic organisms.
• Fish: Fish are vertebrates that live in water. They are a major source of food for humans and other animals. Many fish are benthic organisms.

Benthic organisms are an important part of the aquatic ecosystem. They play a role in the food chain, the cycling of nutrients, and the formation of sediment.