Who built and used the first microscope with magnification of around 300x?

• A. Antonie van Leeuwenhoek
• B. Joseph Lister
• C. Ignaz Semmelweis
• D. Edward Jenner

Answer: (A)

Antonie van Leeuwenhoek is the one who built and used the first microscope capable of around 300x magnification. He crafted tiny, high-quality single-lens microscopes by grinding and polishing glass lenses and mounting them in simple frames. These compact devices could magnify objects about 200–300 times, which allowed him to observe living microorganisms—bacteria, protozoa, and more—in samples like pond water and dental plaque. This hands-on development and use of high-m Magnification lenses opened up the microscopic world for the first time. The other figures are known for medical innovations—Lister for antiseptic surgery, Semmelweis for handwashing to prevent puerperal fever, Jenner for the smallpox vaccine—not for building high-magnification microscopes.