Which branch of science studies microorganisms like bacteria, viruses, and protozoa?

The study of microorganisms such as bacteria, viruses, fungi, algae, and protozoa is known as Microbiology. It is a branch of biology that focuses on living organisms too small to be seen with the naked eye. These microscopic organisms play important roles in our environment, health, and industries.

Microbiology helps scientists understand how microorganisms live, reproduce, and interact with humans, animals, and plants. Some microorganisms are beneficial, while others can cause diseases. For example, Lactobacillus bacteria are useful in making yogurt and cheese, whereas Salmonella can cause food poisoning. Similarly, viruses like influenza and COVID-19 are studied in microbiology to develop vaccines and treatments.

This field is divided into several sub-branches:

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  Bacteriology: Study of bacteria

  
  


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  Virology: Study of viruses

  
  


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  Mycology: Study of fungi

  
  


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  Protozoology: Study of protozoa

  
  


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  Phycology: Study of algae

  
  

Microbiology has many practical applications. In medicine, it helps doctors and researchers identify infectious agents and design antibiotics or vaccines. In agriculture, it aids in soil fertility through nitrogen-fixing bacteria. In environmental science, microbes are used to treat wastewater and decompose organic waste. In biotechnology, microorganisms produce enzymes, vitamins, and antibiotics used in industries.

Other options like Micrology (a non-standard term), Histopathology (study of diseased tissues), and Tavelogy (not a recognized scientific field) are incorrect.
Therefore, the correct answer is Microbiology, the branch of science that studies microorganisms and their effects on life.