The only cell organelle seen in a prokaryotic cell is:

The correct option is B

Ribosomes

The correct option is B.

Explanation of the correct option:

1. Ribosomes have RNA and protein.
2. They are sites of protein synthesis.
3. The only cell organelle seen in a prokaryotic cell is the ribosome.
4. Ribosomes in prokaryotes are of the 70s type.

Explanation of the incorrect options:

Option A:

Mitochondria are found in eukaryotic cells.

Option C:

Plastids are found in eukaryotic cells.

Option D:

Lysosomes are found in eukaryotic cells.

Final answer: The only cell organelle seen in a prokaryotic cell is ribosomes.