Which of the following is an example of amoeboid protozoans?

Which one is the largest unicellular organism?

During conjugation in $Paramecium$,which of the following events occurs?

Which of the following kingdoms does $Paramecium$ belong to?

An $X$ reproduces in such great numbers that the water may appear red,producing red tides and killing large marine animals like $Z$. $X$ belongs to $Y$. Identify $X$,$Y$,and $Z$.

What is the similarity between a trophozoite and an amoeba?