Question

while peering through a microscope, your lab teacher says out loud, \i know that this organism is supposed to be wither a chromalveolate ciliate, a unikont excavate flagellate, or an rhizarian amoeba, but i cant figure out which it is!?\ to which you as a super biology 160 student knowingly reply, thats easy teacher just
...watch and see what it eats.
...all you have to do is see whether it has a nucleus.
...watch how it moves.
...look at its chloroplasts.
...look at how big it is.

Explanation:

To identify the organism (Chromalveolate Ciliate, Unikont Excavate Flagellate, or Rhizarian amoeba), observing movement helps: Ciliates move with cilia, flagellates with flagella, amoebas with pseudopodia. Watching how it moves distinguishes them. Other options: eating (not as distinct), nucleus (all eukaryotes here have nuclei), chloroplasts (not all these groups have them), size (not diagnostic). So the best clue is movement.

Answer:

...Watch how it moves.