Q.

A feature of reproduction that is common to Amoeba, Spirogyra and yeast is that:

1 they reproduce asexually.  
2 they are all unicellular.  
3 they reproduce only sexually.  
4 they are all multicellular.  

Ans.

(1)

Amoeba and yeast are unicellular while Spirogyra is multicellular. But all the three reproduce asexually.