In which of the following are a group of amoeboid cells found?

The 'naked' slime molds are naked -

Match the following columns:

Column-$I$ (Group)	Column-$II$ (Example/Characteristic)
$P$. Chrysophytes	$I$. Euglena
$Q$. Dinoflagellates	$II$. Diatoms,Desmids
$R$. Euglenoids	$III$. Physarum (Slime mold)
$S$. Slime molds	$IV$. Gonyaulax

The visible form of Protista is...

In which animal phylum is the organism $Opalina$ classified?

Two species of Amoeba $X$ and $Y$ were kept in fresh water and adapted to it. Species $X$ developed a contractile vacuole. When both were transferred to sea water and adapted,both $X$ and $Y$ lost their contractile vacuole. From these observations,we conclude that: