Question

1. what type of microscope would you use to visualize a virus? brightfield light microscope, electron microscope, darkfield microscope, phase-contrast microscope

Explanation:

Viruses are extremely small (typically in the nanometer range). Light microscopes (brightfield, darkfield, phase - contrast) have limited resolution (around 200 nm for visible light) and can't resolve viruses. Electron microscopes use electrons instead of light, which have much shorter wavelengths, allowing for much higher resolution (down to atomic scales in some cases), enabling visualization of viruses.

Answer:

B. Electron microscope