Question

based on the diagrams, which organism(s) are eukaryotic and why?

organisms x, y and z, because they are all single - celled.

organisms x and y only, because they have membrane - bound dna.

organisms x, y and z, because they all have dna.

organisms y and z only, because both use flagella for mobility.

Explanation:

Eukaryotic organisms have membrane - bound organelles, including a nucleus that houses membrane - bound DNA. Prokaryotic organisms (like bacteria) have DNA that is not membrane - bound.
Organism X appears to be a prokaryote (e.g., a bacterium) with free - floating DNA. Organisms Y and Z have membrane - bound DNA (as indicated by the nuclear - like structure around the DNA in the diagram).
The presence of a membrane - bound nucleus (membrane - bound DNA) is a key characteristic of eukaryotes.
The fact that an organism is single - celled (Option 1) does not determine if it is eukaryotic (e.g., bacteria are single - celled prokaryotes). The presence of DNA (Option 3) is common to all living organisms (prokaryotes and eukaryotes). The use of flagella for mobility (Option 4) is not a defining characteristic of eukaryotes (some prokaryotes also have flagella).

Answer:

Organisms X and Y only, because they have membrane - bound DNA.