Prokaryotes are the organism which is made up of a cell that does not contain a membrane enclosed nucleus. They have a structure called as nucleiod which looks like a thread in appearance. The eukaryotes are the organism which has membrane bound nucleus.
Among the given list of organism in the options, Methanogens are microorganisms that produce methane as a metabolic result in hypoxic conditions. They are prokaryotic and have a place with the space of archaea.
Apart from this, amoeba, grass and cockroach have membrane bound nucleus.
