Identify the biological specimens shown.

Analysis:

• The image displays three illustrations of microscopic organisms.
• The first illustration on the left appears to be a bacterium, characterized by its rod shape and internal structures. It is labeled with the Cyrillic letter 'Б'.
• The central illustration is an elongated, oval-shaped organism covered in small dots, possibly representing a protozoan like an amoeba or paramecium, or a section of a multicellular organism. It is labeled with the Cyrillic letter 'А'.
• The third illustration on the right shows a more complex, possibly invertebrate, microscopic structure with multiple appendages, resembling a nauplius larva or a similarly complex single-celled organism.

Conclusion:

The image shows biological specimens: a bacterium (labeled 'Б') and two other microscopic organisms (one labeled 'А').