Which of the following have species that can establish symbiotic relat

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.

1 and 2 only
2 and 3 only
1 and 3 only
1, 2 and 3
This question was previously asked in
UPSC IAS – 2021
Option D is the correct answer. All three groups listed – Cnidarians, Fungi, and Protozoa – include species that are known to establish various types of symbiotic relationships with other organisms, including mutualism, commensalism, and parasitism.
Symbiosis refers to a close and long-term interaction between two different biological species. This can include mutualistic relationships (both benefit), commensalistic relationships (one benefits, the other is unaffected), or parasitic relationships (one benefits, the other is harmed).
Examples: Cnidarians like corals have mutualistic symbiosis with zooxanthellae (algae). Fungi form mycorrhizae with plant roots (mutualism) or are components of lichens (mutualism with algae/cyanobacteria). Protozoa include parasitic forms like Plasmodium (malaria) and mutualistic forms like those in termite guts that digest cellulose.