Final answer:
A confocal scanning laser microscope is best suited for viewing thick structures like biofilms because it can focus on one z-plane at a time to construct a 3D image without disturbing the biofilm.
Step-by-step explanation:
The type of microscope that is especially useful for viewing thick structures, such as biofilms, is the confocal scanning laser microscope. Confocal microscopy is advantageous for examining these types of specimens because it utilizes a laser to scan multiple z-planes successively. This process generates a series of high-resolution, two-dimensional images at varying depths which can be assembled into a comprehensive three-dimensional image by computer software. It works particularly well with fluorescent stains to enhance contrast and resolution. Its narrow aperture only allows the light from the focused z-plane to be detected, ensuring image clarity and enabling the observation of structures like biofilms in great detail and without having to fix or slice the specimen, thus preserving the intact biofilm community.