Explanation:

Saccharomyces:
Saccharomyces is a genus of fungi that includes many species of yeast. Yeasts are eukaryotic organisms and have membrane-bound organelles such as mitochondria, Golgi apparatus, endoplasmic reticulum, and vacuoles. Therefore, membrane-bound organelles are present in Saccharomyces.

Streptococcus:
Streptococcus is a genus of bacteria that belongs to the phylum Firmicutes. Bacteria are prokaryotic organisms, which means they lack membrane-bound organelles. Instead, they have simple internal structures such as ribosomes, nucleoid, and plasmids. Therefore, membrane-bound organelles are absent in Streptococcus.

Chlamydomonas:
Chlamydomonas is a genus of green algae that belongs to the phylum Chlorophyta. Algae are eukaryotic organisms and possess membrane-bound organelles. Chlamydomonas cells have a nucleus, chloroplasts, mitochondria, Golgi apparatus, and endoplasmic reticulum. Therefore, membrane-bound organelles are present in Chlamydomonas.

Plasmodium:
Plasmodium is a genus of parasitic protists that causes malaria in humans. Like other protists, Plasmodium is also a eukaryotic organism and possesses membrane-bound organelles. It has a nucleus, mitochondria, Golgi apparatus, endoplasmic reticulum, and apicoplast. Therefore, membrane-bound organelles are present in Plasmodium.

Conclusion:
Among the given options, Streptococcus is the only organism that lacks membrane-bound organelles. It is a prokaryotic bacterium and does not possess complex internal structures like eukaryotic organisms. Saccharomyces, Chlamydomonas, and Plasmodium are all eukaryotic organisms and possess membrane-bound organelles.