The correct option is
C Hydra fuscaHydra fusca ( synonym
: Hydra oligactis ). These are fresh water dwelling organisms. Their association with algae such as zoochlorallae for their nutrition gives them the brown colour.
' So the correct answer is Hydra fusca'
![1004921_649974_ans_65081ac559b04dbf990932cfd75c7756.jpg](https://search-static.byjusweb.com/question-images/toppr_ext/questions/1004921_649974_ans_65081ac559b04dbf990932cfd75c7756.jpg)