Which of the following have species that can establish symbiotic relationship with other organisms? 1. Cnidarians 2. Fungi 3. Protozoa Select the correct answer using the code given below.

Symbiotic relationships involve close and long-term interactions between two different biological organisms. These can be mutualistic (both benefit), commensalistic (one benefits, other unaffected), or parasitic (one benefits, other harmed). All three groups listed exhibit various forms of symbiotic relationships:

1. Cnidarians: Many cnidarians, particularly corals, form a crucial mutualistic symbiosis with photosynthetic algae called zooxanthellae. The algae provide food to the coral, and the coral provides a protected environment for the algae.

2. Fungi: Fungi are well-known for their diverse symbiotic relationships. Examples include mycorrhizae, a mutualistic association with plant roots, where fungi help plants absorb nutrients, and lichens, a mutualistic partnership between a fungus and an alga or cyanobacterium.

3. Protozoa: Many protozoa engage in symbiotic relationships. For instance, flagellate protozoa live in the guts of termites, helping them digest cellulose (mutualism). Other protozoa are well-known parasites, causing diseases in humans and animals, which is a form of symbiosis where one organism benefits at the expense of the other.

Therefore, all three groups have species that establish symbiotic relationships with other organisms.