The development of which type of microscope made it possible to create high-resolution, three-dimensional images of living cells?

A confocal microscope uses focused illumination and optical sectioning to capture sharp images at different depths within a sample. Combining those sections can create a high-resolution, three-dimensional image, and the method can be used to image living cells. A stereomicroscope provides a 3D view but generally does not offer the same high-resolution imaging of cell layers.

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